Section codes for overhead line electrification (OLE) installations: national network

A (one day) comprehensive listing

Last update 21 July 2024

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Traditional numbering system distance and sequence

Code Area Unit Datum Note
A Fenchurch Street-Shoeburyness miles Fenchurch Street
A Newbridge Junction-(Glasgow Queen Street?) km Newbridge Junction Only a short length at Newbridge Junction wired. Now has prefix EG
A Shoeburyness Depot miles Fenchurch Street
A Guide Bridge Station Junction-Crowthorne Junction miles Guide Bridge Station Junction Former DC system, now closed; it appears that this code applied to Ashton Moss North Junction and onto the main (L&Y) line, surviving masts being seen on 30 June 2012
AB Gas Factory Junction-Bow Junction Reported, probably never used. See F
AC (Former) Cornbrook Junction-Trafford Park km Liverpool Central Code may be derived from Allerton Junction to Cornbrook Junction, though not all of this is electrified
ACF Trafford Park Freightliner Terminal km Junction with ACX near Trafford Park West Junction
ACX Trafford Park Yards km Trafford Park West Junction
AE Ashburys Yard miles unknown Former DC system, now closed
AG Allerton East Junction-Garston Junction and Garston sidings miles Euston reversing at Allerton East Junction
AH Allerton Junction-Hunts Cross West Junction miles Liverpool Lime Street
AI Denton Junction-Ashton Moss Junction miles unknown Former DC system, now closed
AL Aston-Lichfield Trent Valley high level km Aston Junction Electrified to 18m 7ch
AN Ashton Moss Yard miles unknown Former DC system, now closed
AR Ashburys Top End Yard miles unknown Former DC system, now closed
AT Tilbury loop miles Fenchurch Street
ATR Barking Riverside branch miles Fenchurch Street Start of flyover has masts in 9 mile region, see this photo
ATX Ripple Lane Depot km start of yard
AW Ardwick Yard miles unknown Former DC system, now closed
AX Allerton Depot miles Liverpool Lime Street
AX Aston Wharf miles Aston Closed 5 April 1980
AY Apperley Junction-Ilkley km St Pancras via Cudworth
B Glasgow High Street-Helensburgh Central via Singer miles Glasgow High Street
B Liverpool Street-Norwich miles/km Liverpool Street Measured in miles to Colchester, then in km to Norwich. B prefix not present Bethnal Green (mast 01 01)-Chelmsford (mast 29 25); some masts thereafter have prefixed and unprefixed plates
B Colchester Depot miles Liverpool Street
B Ashburys East Junction-Romiley (start of line) miles Ashburys East Junction? Code possibly derived from Belle Vue. Former DC system, now dewired
BA Aldersbrook Sidings (Ilford) Numbered from BA01 from junction with up avoiding line, unrelated to distance
BAC Anniesland-Maryhill miles Glasgow High Street Electrified at Anniesland end only
BAT Battersea Wharf Numbered from BAT1 to BAT8, unrelated to distance Temporary wiring for 1960 exhibition probably not energised
BB Birmingham New Street-Bushbury Junction via Wolverhampton miles Birmingham New Street
BB Witham-Braintree km Liverpool Street
BB Dalreoch-Balloch Pier miles Dalreoch Junction
BB Bletchley-Oxford miles Bletchley Electrified at Bletchley end only
BBX Wolverhampton Freightliner Terminal miles Birmingham New Street
BBX Wolverhampton Steel Terminal miles Birmingham New Street Also known as Monmore Green Street Terminal. Dewired early 1990s
BC Colchester-Clacton miles Colchester Junction
BC Bletchley-Cambridge miles Bletchley East Junction Electrified at Bletchley end only, including depot
BC Blackpool North Carriage Sidings km Preston Fylde Junction
BCY Chelmsford Royal Mail Terminal miles Start of branch See also BD
BD Felixstowe Beach Junction-Felixstowe Docks allocated, not used
BE Manningtree North Junction-Manningtree East Junction km Manningtree East Junction
BF East Suffolk Junction-Felixstowe km Liverpool Street Wired at Ipswich end only
BF Asfordby Test Centre Depot km Asfordby North Junction Code derived from Building F, named after UK Coal building converted to test centre
BF King Edward Bridge South Junction-King Edward Bridge East Junction Numbered from BF01 at King Edward Bridge South Junction, unrelated to distance
BG Barking-Gospel Oak km Gospel Oak Junction
BH Hyndland Depot branch miles Partickhill Junction presumed Closed 1987
BH Manningtree South Junction-Harwich km Manningtree South Junction
BHX Harwich Parkeston Yard km Parkeston West Goods Junction
BJ Barnsley Junction Sidings Numbered from BJ01 at junction with main line, unrelated to distance Former DC system, now closed
BJ Bedford-St Johns km Bedford Junction
BK Birmingham New Street-Holliday Street Tunnel miles Derby See also D
BL Lea Junction-High Meads Junction km Lea Junction
BM Stratford Central Junction-Carpenters Road North Junction km Stratford Central Junction defined as 3km
BM Westerton-Milngavie miles Westerton Junction
BP Bescot-Pleck Junction miles Bescot Junction
BR Sheffield Victoria Electric Lay By Sidings miles unknown Former DC system, now closed
BS Birmingham Curzon Street-Stafford (via Aston/Bescot) miles Curzon Street
BS Duddeston carriage sidings/wagon repair shop miles Curzon Street Dewired mid-1980s
BS Singer Works branch miles Singer Works Junction presumed Closed 1 May 1967
BS Sudbury branch allocated, not used
BS Kirkham & Wesham-Blackpool South branch km Preston Fylde Junction Only wired for a short length at Kirkham & Wesham end
BT Channelsea North Junction-Temple Mills East Junction km Channelsea North Junction
BTS Bletchley Top Yard km? unknown Code possibly derived from Bletchley Top Sidings
BTX Stratford Freightliner Terminal km Channelsea North Junction
BU Romford-Upminster km Liverpool St via Romford
BV Norwich Victoria sidings km Liverpool St via Romford
BW Hyndland West Curve miles Hyndland North Junction
BX Norwich Carriage Sidings km Junction with main lines
BXD Bescot Down Side Sidings miles Curzon Street
BXU Bescot Up Side Sidings miles Curzon Street
BY Norwich Thorpe Junction-Great Yarmouth km Norwich Thorpe Junction Only wired for about 1km beside Crown Point Depot
BY Hyndland East Junction-Dalmuir via Yoker miles Hyndland East Junction
BYX Norwich Crown Point Depot km Wensum Junction Sidings 16 and 17 had masts numbered BYX/R/nn, so without a distance element; other sidings measured conventionally
C Lancaster Castle branch Numbering unrelated to distance 1950s scheme; now closed
C Bethnal Green-King's Lynn miles/km Liverpool Street Measured in miles to near mile post 31, then in km to King's Lynn
C Cambridge Depots miles Liverpool Street
C March-Peterborough km Crescent Junction Wired at Peterborough end only
C Cambridge-Lincoln-'North' allocated, not used
C Gorton-Hyde Road Junction Curve miles unknown Former DC system, now closed
C Crewe-Shrewsbury miles Crewe South Junction Code reported in 1964 notice. See also CS
CA Stansted South Junction-Stansted Airport km Stansted South Junction
CB Primrose Hill-Broad Street miles Broad Street Part now de-wired and removed, part now has prefix V, one CB mast remains at Camden Road
CC Bury St Junction-Cheshunt miles Liverpool Street
CE Hackney Downs North Junction-Enfield Town miles Liverpool Street
CE Deal Street Junction-Windsor Bridge South Junction km Deal Street Junction
CF Stansted North Junction-Stansted East Junction km Stansted North Junction
CG Castlefield Junction-Ordsll Lane Junction km Castlefield Junction See also CW
CH Clapton Junction-Chingford miles Liverpool Street
CI Camden Road East Junction-Freight Terminal Junction (Eastern Region portion) km Camden Road Central Junction Line rebuilt, now has prefix YN. See also EN
CI Fairfield-Reddish Numbered from CI01 from Fairfield Junction, unrelated to distance Former DC system, now closed; part used at 25kV AC to feed mobile substation for Manchester Metrolink demonstration
CL Willesden Empty Carriage Lines miles Euston
CL Gresty Lane Junction-Salop Goods Junction miles Euston
CLX Crewe Electric Depot wheel lathe line miles Euston
CM Cheadle Hulme-Macclesfield miles Cheadle Hulme Junction
CN Carlisle-Newcastle km Carlisle South Junction Electrified at Carlisle end only
CN Coventry-Nuneaton miles/km Coventry North Junction Electrified 0m 0ch to 0m 45ch and 9m 30ch to 9m 53ch only. Recent extension of wires at Nuneaton uses km posts, remainder uses miles
CN Calton North Tunnel (Edinburgh) Numbering unrelated to distance Masts in tunnel only, remainder of line uses E
CR Hertford East branch miles Liverpool Street
CR Reddish Depot Numbered from CR01 to at least CR59, unrelated to distance Former DC system, now closed; part used at 750V DC for Manchester Metrolink demonstration
CS Crewe-Shrewsbury miles Crewe South Junction Shown in 1964 notice as C. Electrified to 1m 41ch at Crewe end only
CU Upperby Carriage Depot km Euston
CVL Hardendale Quarry connection km Euston
CVQ Hardendale Quarry line Numbered from CVQ01 from junction with CVL, unrelated to distance De-wired 3 January 1994
CW Castlefield Junction-Windsor Bridge South Junction km Castlefield Junction See also CG
CW Chester-Warrington km Manchester Ship Canal Viaduct Electrified Acton Grange Junction-Arpley Marshalling Yard only
CWX Arpley Marshalling Yard km Arpley Grid Iron Junction
CX Cambridge Carriage Sidings km Liverpool Street
CX Crewe Electric Depot miles Euston
CX Crewe South Yard miles South end of wiring
CX Nene Carriage Sidings (Peterborough) km Peterborough station
D Broad Street lines believed allocated, not used
D Cogload Junction-Rotherham via Bristol, Birmingham, Derby and Chesterfield km Redditch Electrified Kings Norton-Barnt Green only
DA Barnt Green-Redditch km Redditch
DB Birmingham New Street-Kings Norton km Redditch
DC Bescot Curve Junction-Bescot Junction allocated, not used
DD Carlisle Diesel Depot km Euston
DE Stourbridge Junction North-Galton Junction allocated, not used
DE Dunstall Park Junction-Bushbury Junction allocated, not used Possibly electrified at Dunstall Park Junction end. One source also suggests prefix DB. Code not seen on site. See also OB
DED Rugby Midland District Electric Depot Numbered from DED 1, unrelated to distance
DF Derby-Trent allocated, not used
DG Dinting-Glossop miles Dinting West Junction
DH unknown route near Birmingham miles Dudley?
DL Darnall Depot miles unknown Former DC system, now closed
DS Widnes Branch (fast lines) miles Euston
DS Barnt Green-Bromsgrove km Barnt Green Junction
DV Daventry International Rail Freight Terminal (DIRFT) km South end of site
DW Dudley-Wichnor km approximately mile post 4 near Wednesbury Numbered 06km near Walsall counting northwards, but numbered 03km at Ryecroft Junction
DWA unknown route near Walsall km approximately mile post 4 near Wednesbury
DY Dewsnap Sidings miles unknown Former DC system, now closed
E Kings Cross-Aberdeen km Kings Cross Electrified to Saughton Junction only
E Welwyn Garden City Depot km Kings Cross
E East Gate Junction-Colchester Town miles Liverpool Street Officially now EB but at least some masts still carried E in 2010
EB Doncaster-Leeds-Neville Hill Depot km Doncaster Marshgate Junction
EB East Gate Junction-Colchester Town miles Colchester Junction
EBG Harringay Park West Curve km Harringay Park Junction
EBL Hemsworth Loops km Doncaster Marshgate Junction
EBN Leeds Neville Hill Depot km Neville Hill West Junction
EBX Wakefield Cartic Sidings km Doncaster Marshgate Junction
EC Hitchin-Shepreth Branch Junction km Kings Cross
EC Haymarket Central Junction-Gorgie Junction km Kings Cross
EC Euston Empty Carriage Lines miles Euston
ECF Hitchin (Cambridge Flyover) km Hitchin North Junction
ECX Craigentinny Depot km East end of depot (and at least one mast measured from Kings Cross)
ED Euston Down Side Carriage Sheds miles Euston
EDX Doncaster Carr Depot km South end of site
EG Edge Hill Upper Reception Sidings miles Edge Hill East Junction
EG Gridiron Goods Lines miles Start of branch Same as Edge Hill Upper Reception Sidings?
EG Saughton Junction (near Edinburgh)-Glasgow Queen Street km Glasgow Queen Street
EGA Eastfield depot km South end of depot
EGM Cowlairs West Junction-Cowlairs North Junction km Cowlairs West Junction Electrified at Cowlairs West Junction end only. Datum defined as 2km
EGN Cowlairs East Junction-Cowlairs North Junction km Cowlairs East Junction Electrified at Cowlairs East Junction end only. Datum defined as 3km
EH Hertford Loop km Kings Cross
EJ Greenhill Upper Junction-Greenhill Lower Junction km Greenhill Upper Junction
EL Parkside Junction-Lowton Junction km Parkside Junction
EM Finsbury Park-Moorgate km Moorgate Electrified to Drayton Park (down line)/Highbury & Islington (up line) only. Up line wiring supports between Drayton Park and Highbury not numbered
EN Norton Bridge-Stone miles Stone Shown in 1964 notice as SG
EN Camden Road East Junction-Freight Terminal Junction (Midland Region portion) km Regional boundary Datum defined as 1km. Line rebuilt, now has prefix YN. See also CI
EP Polmont-Larbert Junction km Polmont Junction
ER Grangemouth Junction-Grangemouth Refinery km Grangemouth Junction Electrified to just before NR/refinery boundary only
ERB Kings Cross platform 0 Numbered ERB 01 to ERB 13 from buffer stops, unrelated to distance
ES Stirling-Alloa km Stirling Middle Junction
ESP Kings Cross Canal Tunnels km St Pancras Junction
ET Doncaster-Hull km Marshgate Junction Electrified for short length at Doncaster end only
EU Euston Up Side Carriage Sheds miles Junction with G
EW Portobello Junction-Monktonhall Junction via Newcraighall km Monktonhall Junction
EWA Low Fell Junction-Norwood Junction km Low Fell Junction
EWD Millerhill EMU depot km Junction with up Millerhill line
EX Kings Cross Freight Terminal km Kings Cross Dewired 19 August 2001
EX Hornsey Carriage Sidings and Bounds Green Depot (including lines to former Palace Gates station) km Kings Cross
EX Ferme Park Down Sidings km Kings Cross
EX Peterborough Eastfield Sidings km Kings Cross
EX Retford down side sidings km Kings Cross
EXA Alnmouth Engineer's Sidings km Junction with main line
EXB York Works km York Yard North Junction
EXD Doncaster Yard km Loversall Carr Junction
EXD Doncaster Loversall Junction-Decoy North Junction km Loversall Carr Junction
EXE Edinburgh Yard (Millerhill Depot) believed allocated, not used
EXE Doncaster Up West Reception Line km Decoy North Junction
EXF Doncaster Belmont Yard km South end of wires Part not electrified
EXG York avoiding line km Holgate Junction
EXH York Yard head shunt km Holgate Junction
EXK Northallerton Up Sidings km Junction with main line
EXR Tyne Yard km Park Lane Junction
EXS Peterborough Spital Sidings km Junction with EX
EXT Newcastle King Edward Bridge North Junction-Newcastle East Junction (High Level Bridge) km King Edward Bridge South Junction
EXU Newcastle King Edward Bridge North Junction-King Edward Bridge East Junction km King Edward Bridge North Junction
EXV Heaton Depot (south) km Heaton South Junction
EXW Heaton Depot (north) km Heaton South Junction
EXX Heaton Depot service road 4 km Marsh Lane Junction
EXY York Yard km
EXZ Berwick Down North Sidings km Junction with main line
EY Bounds Green Repair Shed km Kings Cross
EYX Alnmouth Up Side Sidings believed allocated, not used
EZ Drem-North Berwick km Drem Junction
F Glasgow High Street-Drumgelloch-Saughton Junction miles/km Glasgow High Street/'Garrowhill' Newbridge Junction-Saughton Junction re-coded EG from 2017 Measured in miles from High Street to just east of Airdrie, then in km but with continuous numbering putting the change over point at '11km', giving a false zero near Garrowhill
F St Pancras-Clay Cross km St Pancras Electrified to Bedford only; extension northwards uses SPC1
F Denbigh Hall South Junction-Bletchley flyover miles Bletchley Flyover Junction Code changed to FX
F Gas Factory Junction-Bow Junction miles Fenchurch Street Original code. See also AB
FA Cricklewood-Acton Lane allocated, not used
FB Forest Gate-Barking miles Forest Gate Junction
FB Glasgow High Street-Bridgeton Central miles High Street Junction Wired 7 November 1960; closed 1987
FBA Barking Bay Platform 1 km Barking Station Junction Datum defined as 1km
FBD Bathgate Depot km Glasgow High Street/'Garrowhill' Measured in miles from High Street to just east of Airdrie, then in km but with continuous numbering putting the change over point at '11km', giving a false zero near Garrowhill
FCB Farringdon-City Thameslink km Farringdon Junction Possibly allocated as far as Blackfriars
FCX See FXC
FD Luton-Dunstable allocated, not used Link to main line not listed
FG Bedford-Bletchley allocated, not used
FH Leeds Station-Holbeck Code changed to LE
FL Farington Junction-Lostock Hall Junction km Farington Junction
FM See MF
FP Hornsey EMU Depot Numbered FP01 to FP125 from south end of site, unrelated to distance
FS Bellgrove-Springburn-Cowlairs West Junction miles Bellgrove Junction
FS Shenfield flyunder miles Liverpool Street Not seen on site; see also L
FT Sighthill East Junction-Garnqueen North Junction km Sighthill East Junction
FW Holbeck East Junction-Wortley West Junction allocated, not used
FW Cowlairs Chord km Cowlairs South Junction
FX Gartcosh Curve km Gartcosh Junction
FX Denbigh Hall South Junction-Bletchley flyover miles Bletchley Flyover Junction Code was F
FXB Bedford Cauldwell Road Depot km Bedford South Junction
FXC Cricklewood Depot km St Pancras Also erroneously recorded as FCX
FXS Bedford Depot stabling sidings [near station] km North end of yard
FXW Bedford Depot carriage washer lines km North end of yard Note that the washing machine itself beside the main line carries F masts
FY Finnieston West Junction-Finnieston (Exhibition Centre) Station (Up Argyll Line) km Stobcross Tunnel Most masts do not carry identification
G Glasgow Central-Eglinton Street Junction miles Glasgow Central Masts are numbered from G/0/1 upwards across the Clyde covering all lines to Bridge Street Junction, and then continue to Eglinton Street Junction. Here they meet G-series masts counting from Euston. Originally, the 'Glasgow' count continued to Lesmahagow Junction with the 1960s electrification, being renumbered in 1974 to the 'Euston' count
G Euston-Eglinton Street Junction (including Crewe carriage shed/Brook sidings/Preston North Union yard) miles/km Euston Measured in miles to Weaver Junction, then in km northwards. Part dewired 2000/01? Masts are numbered from G/0/1 upwards across the Clyde covering all lines to Bridge Street Junction, and then continue to Eglinton Street Junction. Here they meet G-series masts counting from Euston. Originally, the 'Glasgow' count continued to Lesmahagow Junction with the 1960s electrification, being renumbered in 1974 to the 'Euston' count
G Carstairs Sidings km Euston Code not carried
G Nuneaton up sidings miles Euston Lifted ≈2003
G Glossop-Hadfield miles Glossop? Former DC system. Now DG?
G lone mast at Birmingham International miles Euston Remainder of line uses GB
G Bounds Green Depot km Kings Cross Reported but believed used in error, should be EX
GA Watford Junction-St Albans Abbey km Watford Junction
GA Milnwood Junction-Mossend East Junction km Mossend East Junction
GB Rugby-Birmingham New Street miles Euston
GB Birmingham Curzon Street branch and mail sidings miles Euston Dewired mid-1980s
GB Springs Branch-Bamfurlong flyunder km Bamfurlong Junction
GB Mossend South Junction-Mossend West Junction km Mossend South Junction
GB Carnforth-Barrow km Euston Electrified at Carnforth end only
GBX Bamfurlong sidings miles Bamfurlong Sidings Junction
GC Crewe-Chester miles Euston Electrified Crewe to Steelworks Junction only
GC Cathcart Circle miles Eglinton Street Junction (anticlockwise) Some masts renumbered in K series
GC Gorton-Hyde Road Junction Numbered from GC01 (from Gorton Junction?), unrelated to distance
GCW Crewe Works miles Junction with Chester line at works entrance
GD Motherwell-Dunblane including Mossend Yard km Motherwell Lesmahagow Junction Electrified to 123m 33ch
GDC Carmuirs West Junction-Carmuirs East Junction km Carmuirs East Junction
GDM Motherwell Depot km South end of depot
GE Glossop-Hadfield miles Glossop Former DC system, now HJ
GE Winwick Junction-Earlestown km Winwick Junction
GE Carstairs East Junction-Edinburgh Haymarket East Junction (including access to Slateford sidings) km Carstairs East Junction North end originally an extension of E
GEN Carstairs Station Junction-Carstairs East Junction km Carstairs Station Junction
GES Carstairs East Junction-Carstairs South Junction km Carstairs South Junction
GF Gushetfaulds Junction-Gushetfaulds Freightliner Terminal miles South end of depot? Now de-wired
GF Rutherglen East Junction-Whifflet North Junction km Rutherglen East Junction
GG Langloan Junction-Coatbridge Junction km Langloan Junction
GH Hamilton Loop km Motherwell Lesmahagow Junction
GHL Larkhall Branch km Haughhead Junction
GJ Cathcart West Junction-Neilston miles Cathcart West Junction
GK Cathcart North Junction-Newton West Junction miles Cathcart North Junction
GL Cathcart East Junction-Cathcart West Junction miles Cathcart East Junction
GL Garston Yard (Speke Junction area) miles unknown Now carries prefix LX
GL Weaver Junction-Liverpool Lime Street miles Euston First approximately 2 miles (GL175/nn to GL176/62) over flyover as far as M56 bridge, see also L
GM Crewe-Manchester Oxford Road miles Euston First few masts to about 159 mile post, see also M
GM Uddingston Junction-Law Junction via Holytown km Law Junction
GN Mossend North Junction-Mossend East Junction (Fullwood Junction) km Mossend East Junction
GNA Little Bridgeford Junction-Lower Heamies km Euston
GNB Searchlight Lane Junction-Yarnfield Junction km Euston
GO Gulf Oil branch miles Birmingham New Street
GP Shieldmuir Junction-Wishaw Central Junction km Wishaw Central Junction
GPD Polmadie Depot Downside sidings km South end of depot
GPU Polmadie Depot Upside Sidings allocated, not used (sidings use G)
GRM Shieldmuir Royal Mail Terminal loop km South end of loop
GS Lanark branch km Lanark Junction
GT Holytown Junction-Midcalder Junction km Holytown Junction
GT Gasworks Tunnel Numbered from GT01 at south end of tunnel, unrelated to distance
GW Shields Junction-Larkfield Junction miles Larkfield Junction
GW Glossop West Curve Numbered from GW01 at Dinting South Junction, unrelated to distance Former DC system, now DG
GX Bletchley Up Yard carriage sidings miles Euston
GX Crewe Down Independent lines miles Euston
GX Crewe Basford Hall Up Sidings miles Euston
GX Nuneaton Down Sidings miles Coventry North Junction/Euston (sources disagree)
GX Over & Wharton Branch miles Euston Electrified at Winsford end only
H Marylebone lines allocated, not used
H Didcot East Junction-Bordesley Junction via Oxford allocated, not used
HB Perry Barr North Junction-Perry Barr West Junction miles Perry Barr North Junction
HC Macclesfield Hibel Road-Colwich miles Macclesfield Hibel Road
HD Smethwick West-Bordesley South Junction via Moor Street allocated, not used
HF Halton Junction-Frodsham Junction miles Halton Junction Electrified at Halton Junction end only. Early code since replaced, or allocated not used? - code now LC
HG Huyton-Wigan km unknown
HH Hartford LNW Junction-CLC Junction miles Hartford LNW Junction Electrified at Hartford LNW Junction end only
HJ East side of Dinting triangle miles Dinting South Junction
HK Coventry-Leamington Spa via Kenilworth allocated, not used
HL Colne Junction-Hythe Junction miles Starts at 1 mile at Colne Junction
HN Haymarket North Tunnel Numbering unrelated to distance Fixings in tunnel only, remainder of line uses E
HO Spur through Hyde North miles unknown Former DC system, now closed
IL Ilford carriage sheds Numbered IL01 to IL66C from west end of site, unrelated to distance
IMG Bamfulong Sidings Junction-Ince Moss Junction km Bamfulong Sidings Junction
J Paddington-Heathrow Airport Junction km Paddington Code originally allocated as far as Swansea, see MLN, RW, SWB and BSW for 2015 scheme. See also OBR
JB Maidenhead-Bourne End branch km Paddington
JH Heathrow Airport Junction-Heathrow Terminal 4 km Paddington
JJ Heathrow Terminals 1, 2, 3-Heathrow Terminal 5 km Paddington
JW Acton Poplar lines km East end connection with J
JW Slough-Windsor & Eton branch km Paddington
JX Old Oak Common Crossrail depot km Paddington
K Reading-Penzance (via Berks and Hants Line) allocated, not used
K Muirhouse Junction-Kilmarnock km Glasgow Central (original)/Muirhouse Central Junction (later renumbering before OLE used)
KA Reading [new] depot km Paddington Most masts changed to NEW, though some KA remained. Code changed to RTD
KB Busby Junction-East Kilbride km Busby Junction
KC Coventry-Leamington Spa miles Leamington Spa Electrified at Coventry end only
KC Kidsgrove-Crewe miles Kidsgrove Junction
KC Crewe North Staffordshire curve miles Euston Closed 1 October 1984
KLS King's Lynn Sidings km Liverpool Street
KYD Kingmoor Down Yard km Euston Code sometimes listed as KD in error
KYU Kingmoor Up Yard departure lines km Euston
L Glasgow Bridge Street Junction-Gourock miles Glasgow Bridge Street Junction
L Glasgow Smithy Lye sidings miles Glasgow Bridge Street Junction Dewired 2007
L Letchworth sidings Numbered from L01 to L29, unrelated to distance
L Weaver Junction-Liverpool Lime Street miles Euston From L177/01; see also GL
L Shenfield flyunder miles Liverpool Street LNER code still used; see also FS
L Colchester flyunder miles Liverpool Street NER code still used
LA Paisley-Ayr km Ayr side of Paisley Gilmour Street station
LA Leeds West Junction-Engine Shed Junction km Leeds North Junction
LAX Ayr (Townhead) Sidings km Junction with main line
LB Largs branch km Kilwinning Junction
LC Shields Junction-Paisley Canal miles/km Glasgow Bridge Street/'Shields Junction' Measured in miles from Glasgow Bridge Street to Corkerhill depot, then in km but with continuous numbering, giving a false zero near Shields Junction
LC Halton Junction-Frodsham Junction km Halton Junction Electrified for a short length at Halton Junction end only Code previously HF
LCN Lostock Junction-Crow Nest Junction km Manchester Victoria
LCX Corkerhill Depot sidings miles unknown
LD Byrehill Junction-Dubbs Junction km Dubbs Junction
LD BREL York Works test track Numbering unrelated to distance (and possibly not even related to number of masts)
LD Leighton Buzzard-Dunstable North miles Leighton Buzzard Electrified at Leighton Buzzard end only
LE Leeds Whitehall Junction-Engine Shed Junction km Whitehall SW Junction Code was FH
LG Willesden Low Level Goods Line miles Euston
LH Liverpool Edge Hill-Hull via Manchester Victoria and Leeds km Liverpool Edge Hill Electrified Leeds Whitehall Junction-Copley Hill West Junction only
LL Crewe Low Level lines miles Euston
LL Salop Goods Loop Junction-Gresty Lane Junction miles Euston
LM Liverpool-Manchester miles/km Liverpool Lime Street Only wired from Edge Hill. Originally electrified to Olive Mount Junction measured in miles and Earlestown-Deal Street Junction in km, since 2015 all wired in km
LM Hunts Cross-Hunts Cross West Junction, plus short stretch towards Garston miles Liverpool Lime Street
LN Ardrossan Harbour branch km Holme Junction
LO Godley Junction-Apethorne Junction miles unknown Former DC system, now closed
LS Leeds-Skipton km St Pancras via Cudworth
LS Glasgow Shields Depot East end of site
LS Lawton Branch miles Lawton Junction Electrified at Sandbach end only; now closed
LW Wemyss Bay branch miles Wemyss Bay Junction
LW Huyton-Wigan (Springs Branch Junction) allocated, not used
LX Downhill Carriage Sidings [Edge Hill] miles Euston
LX Halewood Ford Plant miles Euston
LX Runcorn-Folly Lane branch miles Runcorn De-wired 13 March 1994
LX Garston Speke Down Sidings miles Euston
LXA Ditton/Widnes Alstom Train Care Centre km East end of site
LXB Ditton/Widnes Alstom Train Care Centre arrival/departure line km East end of site
LY Micklefield Junction-Church Fenton North Junction allocated, not used
M Lancaster Green Ayre-Morecambe Numbering unrelated to distance, believed to run M1 to M178 from Green Ayre 1950s scheme; now closed. Experimental masts carried X
M Crewe-(almost) Deansgate miles Euston See also GM
M Stub of Heaton Norris-Guide Bridge branch miles Euston Masts are all M183 71, with suffix A to P
M Mottram Yard miles unknown Former DC system, now closed
MA Manchester Oxford Road-Altrincham miles Euston (main line use)/Manchester Oxford Road Junction (Metrolink use) Code reused for Manchester Metrolink, still used Deansgate-Cornbrook Junction. Also appears to have had masts in the the form MA804, numbering unrelated to distance
MAS Manchester Airport south curve km Heald Green South Junction
MB Manchester-Bury allocated, not used Does not apply to Manchester Metrolink
MC Mound [Centre] Tunnel (Edinburgh) Numbering unrelated to distance Fixings in tunnel only, remainder of line uses E
MD Manchester International Depot miles Euston
MF Kentish Town-Moorgate km Moorgate Now de-wired and line closed east of Farringdon. Also reported as FM: possibly originally intended code; MF carried and seen in official documentation; FM not seen on site
MG Salford Crescent-Euxton km Manchester Victoria
MH Ardwick-Hadfield miles Ardwick Junction See also OB
MHX Ardwick Depot km Junction with MH
MIA Heald Green North Junction-Manchester International Airport km Heald Green North Junction
ML Euxton Junction-Manchester Deal Street Junction via Bolton allocated, not used
MO Mottram Yard miles unknown Former DC system, now closed
MP Merchant Park stabling lines km Junction with TT? Hitachi Newton Aycliffe IEP factory
MR Mottram Yard miles unknown Former DC system, now closed
MS Mottram Sorting Sidings miles unknown Former DC system, now closed
MS Manchester-Sheffield miles unknown Former DC system, now closed. Only used to Hadfield?
MS Guide Bridge-Stalybridge km Manchester Piccadilly
MT Muirhouse Central Junction-Terminus Junction km Muirhouse Central Junction
MVL Manchester Victoria-Stalybridge km Manchester Victoria
MWL Longsight wheel lathe roads miles Euston
MX Manchester Longsight Depot carriage sheds miles Euston
MX Goostrey Shell Mex sidings miles Euston
MX (Adswood?) sidings (near 182 mile post near Stockport) miles Euston
MX Manchester Mayfield Parcels Depot miles Euston
MXH Manchester Longsight Depot outer roads ('old coal yard') miles Euston
N Water Orton East Junction-Norwich via Leicester, Ely and Peterborough km Water Orton East Junction Electrified for short section north and south of Nuneaton only (to mast N/22/10); Nuneaton station is G
NA Nuneaton-Whitacre Junction miles Whitacre Junction Shown in 1964 notice as O. Electrified for small section of Nuneaton Abbey curve only
NEW Reading [new] depot km Paddington Code changed to RTD
NOC Normanton-Colton Junction km York
NPD North Pole Depot Departure Road km Junction with NPW (just east of West London Line bridge)
NPE North Pole Depot East Side km Junction with NPW (just east of West London Line bridge)
NPM North Pole Depot Maintenance Shed km Junction with NPE (near east end)
NPW North Pole Depot West Side km West end of yard
NPX North Pole Depot East Sidings/Wheel Drop km unknown
NS Derby Etches Park depot km St Pancras
NW Nuneaton-Wigston Junction miles Nuneaton South Junction Electrified at Nuneaton end only. Now dewired
NX Northampton Down Side Sidings miles Euston Rebuilt as maintenance depot, retains prefix
NX Northampton Siemens Traincare Depot miles Euston
NXG New Cross Gate depot km Surrey Quays end of track Single overhead track for testing trains; five masts total
O Nuneaton-Whitacre Junction miles Whitacre Junction Code reported in 1964 notice. See also NA
OB Ardwick-Hadfield A few masts under the M60: numbered 'OB 18B <individual number>'. See also MH
OB Dunstall Park Junction-Bushbury Junction allocated, not used? Possibly electrified at Dunstall Park Junction end only. Thought to refer to masts under a bridge only, remainder of route is DE
OBR Paddington-Swansea km Paddington Some masts under bridges only, remainder of route is J
P London Marylebone-Birmingham Snow Hill allocated, not used
PA Neasden Midland-Neasden Junction allocated, not used
PB Preston-Blackpool km Preston Fylde Junction
PD Pleck Junction-Darlaston Junction miles Darlaston Junction
PG Newton-le-Willows Junction-Golborne Junction km Newton-le-Willows Junction
PH Soho South Junction-Perry Barr South Junction miles Perry Barr South Junction
PH Pelaw-Sunderland km Pelaw Network Rail element of Tyne & Wear Metro route; DC system
PHS Sunderland-South Hylton km Pelaw Also appears to have numbers of the form 'O/BR014' (applied to masts attached to bridges and based on their numbers). Network Rail element of Tyne & Wear Metro route; DC system
PHX Sunderland station km Pelaw Also appears to have numbers of the form 'O/BR255' (applied to masts attached to bridges and based on their numbers). Network Rail element of Tyne & Wear Metro route; DC system
PT Wolverhampton-Portobello Junction miles Portobello Junction
RB Rugby-Leamington line miles Rugby Electrified to mast RB/0/15 at Rugby end only
REG Reading Station Individually numbered, unrelated to distance 'Masts' attached to new footbridge
RF Finnieston East Junction-Rutherglen km Rutherglen Central Junction
RG Ryecroft Junction-Rugeley km Ryecroft Junction
RM Warrington Dallam Royal Mail Terminal miles Euston Note that the measuring unit is not the same as that used on masts on the adjacent main line
RR Roade-Rugby via Northampton miles Euston
RS Reading Feeder Lines (Reading Station-Oxford Road Junction via new route through old depot site) km Paddington Code changed to RFR There exist drawings where the mast km counts up away from Paddington, but the individual masts within that km count up towards Paddington
RS Reading West Curve km Paddington via Reading West Junction (reverse) Code changed to RWC There exist drawings where the mast km counts up away from Reading West Junction, but the individual masts within that km count up towards Reading West Junction
RS Reading East Curve (Westbury lines) km Paddington Code changed to BKE There exist drawings where the mast km counts up away from Paddington, but the individual masts within that km count up towards Paddington
RT Tilbury East Junction-Tilbury South Junction-east side sidings miles Tilbury East Junction Official code, see also TR. Route now closed
RTS FF Romford OLE Depot Numbered from west end of site, unrelated to distance Code possibly derived from Romford Training Span, Furrer+Frey (type of OLE design). Dewired in May 2011
RW Rutherglen West Curve km Rutherglen West Junction
RW Great Western Main Line km Paddington Reading station area only from 56km to ≈60.5km. Code changed to MLN
RX Rugby Peterborough Branch siding miles Euston Progressively dewired from 1966
RY Rugby-Peterborough line miles Rugby Electrified to mast RY/01/02 at Rugby end only
S Shenfield-Southend miles Liverpool Street LNER code still used
S Southend Victoria Depot miles Liverpool Street
S Wilmslow-Slade Lane Junction (Styal Loop) miles Wilmslow Code reported in 1958 notice. See also SO
S Reading West Curve Flyover Individually numbered, unrelated to distance 'Masts' attached to new flyover under new main lines
SA Stechford-Aston miles Stechford
SA Willesden Sudbury Arrival Sidings miles Euston
SA East Ham Depot km Fenchurch Street Believed used for masts in sheds, remainder use A
SB Stockport-Buxton miles Edgeley Junction Electrified to Hazel Grove only
SB Shipley-Bradford Forster Square km St Pancras via Cudworth
SC Stratford Central Junction-Copper Mill Junction km Stratford Central Junction
SC Skellow Junction-Carcroft Junction allocated, not used
SC Slateford Junction-Craiglockhart Junction allocated, not used
SC unknown route near Crewe miles Euston
SCX Temple Mills Yard km Stratford Central Junction Now dewired
SCX Stratford Orient Way Sidings km Junction with main line
SCZ Temple Mills Yard km Junction between East Yard and West Yard? Now dewired
SE Shipley-Guisley km Esholt Junction See also TUN No 1; TUN No 2 and TUN No 19
SG Norton Bridge-Stone miles Stone Code reported in 1964 notice. See also EN
SG Speke Junction-Garston Dock and Speke Yard miles Euston
SG Stonebridge Park Sidings miles Euston
SGD Stoke Gifford depot km East end of depot
SHED Three Bridges depot Numbered SHED01 to SHED11 unrelated to distance See also TBD
SN Sandbach-Northwich miles Sandbach Electrified at Sandbach end only
SO Wilmslow-Slade Lane Junction (Styal Loop) miles Wilmslow Shown in 1958 notice as S
SO Guide Bridge West Junction-Dukinfield Numbering unrelated to distance Former DC system, now closed
SP lone mast near Heathrow flyover km Paddington
SPC2 Bedford 50 mile post-Wellingborough km St Pancras See also SPC2 where registration plates give km and decimal, not km and sequence number
SS Wickford-Southminster km Liverpool Street
SS Soho North Junction-Soho East Junction miles Soho East Junction
ST Seven Sisters Junction-South Tottenham West Junction miles South Tottenham West Junction Two sequential masts near Seven Sisters Junction are numbered ST 0 11 and ST 1 12
SW Stafford-Wellington miles Uttoxeter Line Junction Electrified at Stafford end only; remainder of line lifted
SW Shipley West Curve km Shipley South Junction
SW Crewe Works Traverser One line, two masts only
SX Stafford Salop Sidings miles Euston
SX unknown route near Crewe miles Euston
T Torresholme triangle southbound curves (Lancaster) Numbering unrelated to distance 1950s scheme; now closed. Probably includes route south to Heysham
T Tinsley Yard miles unknown Former DC system, now closed; dewired ≈1968
T Tunnels on Woodhead route miles unknown Former DC system, now closed
TB Tottenham and Hampstead Line miles St Pancras via Upper Holloway Only wired at Woodgrange Park Junction end. Relabelled BG in 2018
TBD Three Bridges depot Single switching mast numbered TBD 01F Remainder of line uses SHED
TC Tottenham South Junction-South Tottenham West Junction miles Tottenham South Junction South Tottenham East Junction-South Tottenham West Junction relabelled BG in 2018
TD Temple Mills Eurostar Depot connecting line km Stratford International station
TE unknown route near Thorpe le Soken; probably reported in error for TW. Masts numbered in 16/17 mile region miles Colchester Junction
TF Tilbury Freightliner yard Numbered from TF01 from Grays East Junction, unrelated to distance
TG Carlisle Through Goods Line km Upperby Bridge Junction Now electrified Upperby Bridge Junction-Upperby Junction; formerly electrified to Caldew Junction
TH Thornton Field sidings Numbered from TH01A to TH48 from Thornton Field Junction, unrelated to distance Dewired June 2008
TM Temple Mills Eurostar Depot km Stratford International station
TM Long Marston depot km south end of wiring Masts were spares from Temple Mills depot and conveniently suggest 'Test Mast'. Few masts on east side of loop
TMD Stratford Traction Maintenance Depot km Stratford Central Junction East Now closed
TP Tinsley-Parkgate km Tinsley junction with tram system DC system. Network Rail element of Sheffield Tram-Train route; counts from TP 00 11 at Supertram boundary, continuing from TP0010 under the Supertram numbering system
TR Tilbury Riverside Triangle (West Side) miles Fenchurch St via Dagenham Dock Now dewired
TR Tilbury East Junction-Tilbury South Junction-east side sidings miles Tilbury East Junction Code actually carried, see also RT. Route now closed
TS Preston Dock Street Sidings OLE Depot km North end of yard Code derived from 'Training Span'
TS Romford OLE Depot km West end of yard Code derived from 'Training Span', dewired in May 2011
TS Rugby On Track Machine Depot km? Junction with former Peterborough branch Code derived from 'Training Span'
TS Willesden Princess Royal Distribution Centre Numbered from TS01 at south end of site, unrelated to distance Code derived from 'Terminal Shed'
TSA Sutton Tunnel Numbering unrelated to distance Masts in tunnel only, remainder of line uses AL
TSR Swindon electrification training school km East end of site Initially no mast plates used, added by late January 2016
TT Alstom Midlands Test Centre km Asfordby tunnel north portal Code derived from 'Test Track'
TT Hitachi Newton Aycliffe IEP factory km Parkgate Junction Code derived from 'Test Track'. Some individual mast plates are mounted out of sequence
TUN No 1 Baildon No 1 Tunnel Numbered from TUN No 1 01 at north end, unrelated to distance Remainder of route is SE
TUN No 2 Baildon No 2 Tunnel Numbered from TUN No 2 01 at north end, unrelated to distance Remainder of route is SE
TUN No 19 Esholt Tunnel Numbered from TUN No 19 01 at north end, unrelated to distance Remainder of route is SE
TW Thorpe le Soken-Walton on Naze miles Colchester Junction
UG Upminster-Grays miles Upminster Junction
UL High Level Goods Line miles Euston
V Carpenters Road South Junction-Camden Junction km Camden Junction (on West Coast Main Line)
VC Reading Lane Junction-Navarino Road Junction km Navarino Road Junction
VE Finsbury Park-Canonbury Numbered from VE01 from Canonbury West Junction, unrelated to distance
VL Manchester Victoria-Leeds km Liverpool Lime Street
VS Channelsea South Junction-Stratford km Channelsea South Junction
VW Channelsea-North Woolwich allocated, not used
W Wath branch miles Barnsley Junction Former DC system, now closed
WA Edge Hill Wapping Branch miles Junction with main line
WB West London Junction (Willesden)-North Pole miles West London Junction Now WE
WB Willesden Brent Sidings miles Euston De-wired 1990s
WBX Brent Sidings miles Euston
WC Willesden Carriage Sidings/Wembley Traincare Depot miles Euston
WD Willesden Traction Maintenance Depot miles Euston
WE West London Junction (Willesden)-Kensington Olympia km West London Junction Formerly WB. Electrified to 4m 73ch only
WE Wath Exchange Sidings Numbering unrelated to distance Former DC system, now closed
WF Willesden Freightliner Terminal miles South end of site
WG Camden Road Junction-(a little south of) Acton Central km Camden Road Junction
WH Kensal Green Junction-Willesden Low Level Station km Kensal Green Junction Electrified at Kensal Green Junction end only
WI Ordsall Chord km junction with LM
WJ Kensal Green Junction-Willesden Junction (City Goods Line) km Kensal Green Junction
WK Willesden High Level Junction-Mitre Bridge Junction km Willesden High Level Junction
WL Earlestown South Junction-West Junction km Earlestown South Junction
WL Acton Wells Junction-West London Junction allocated, not used
WM Acton Wells-Willesden Freight Terminal Junction km Acton Wells Junction Small portion electrified at Acton Wells end
WN Acton Wells-Acton East Junction allocated, not used
WN Niddrie North Junction-Niddrie West Junction allocated, not used
WP Water Orton Junction-Park Lane Junction allocated, not used
WR Great Western Main Line km Paddington Single mast seen west of Iver and also near Reading West; remainder of line MLN
WS Niddrie South Junction-Niddrie West Junction allocated, not used
WS Wolverhampton North Junction-Oxley Carriage Sidings miles Wolverhampton North Junction
WS Whifflet South Junction-Sunnyside Junction km Whifflet South Junction
WS Watford-St Albans miles Watford Watford sidings only now with this prefix; remainder now GA
WS Wigan-Salford km Manchester Victoria
WSL Oxley Low Level Carriage Sidings km South end of site
WSX Oxley Carriage Sidings km South end of site
WTX Willesden Wembley Train Operations Centre miles End of yard
WW Wavertree Junction-Wapping Branch miles Wavertree Junction Now closed
WW Wath West Departure Sidings Numbering unrelated to distance Former DC system, now closed
WX Wavertree Yard miles Euston
X Grantham down side sidings km Grantham South Junction
X Ovangle Bridge-Carlisle Bridge (Lancaster area) Numbering unrelated to distance 1950s scheme experimental masts, others were M; now closed
X Cowlairs West Junction-Dundee Central Junction allocated, not used
X Crewe sorting sidings south down arrival line miles Euston
X Swansea Maliphant depot km North end buffer stops Masts in place but no wiring installed
XC Carmuirs East Junction-Larbert Junction allocated, not used
XEB Wakefield Wrenthorpe Sidings km Doncaster Marshgate Junction
XG Gartcosh Junction-Gartsherrie South Junction allocated, not used
XO Walsall tunnel Numbered from XO/01 from south end, unrelated to distance
XP Polmont Junction-Carmuirs West Junction allocated, not used
XQ Greenhill Lower Junction-Greenhill Upper Junction allocated, not used
XR Crossrail central section km Paddington Presumed, see XRA. Plan (erroneously?) shows 69km at Great Western Main Line junction
XRA Crossrail Abbey Wood branch km Paddington
XRS Crossrail Plumstead Stabling Sidings km Paddington
XRW Crossrail link onto Great Western Main Line km junction with J
XX See XX below
Y St Pancras-Channel Tunnel boundary km St Pancras
Y Channel Tunnel boundary-Dollands Moor-Saltwood Tunnel km St Pancras? Code changed to YS
YA Ashford station loop of Channel Tunnel Rail Link km Ashford West Junction
YAX Dollands Moor Yard km St Pancras?
YC Silo Curve (link from St Pancras to North London Line) km St Pancras
YD Yoker Depot miles East end of depot
YD Freight line from CTRL to Dollands Moor yard km Dollands Moor West Junction
YF Singlewell Junction-end of OLE near Fawkham Junction km Singlewell Junction Datum defined as 200km
YK Ebbsfleet-Springhead Junction km Ebbsfleet
YKX Ebbsfleet Church Path Pit sidings (later known as Ebbsfleet turnback sidings) km Junction with YK near Ebbsfleet
YN North London (Kings Cross) Incline km Camden Road Central Junction or Copenhagen Junction?
YR Ripple Lane chord km St Pancras
YRX Ripple Lane exchange sidings km Renwick Road Junction
YS Channel Tunnel boundary-Dollands Moor-Saltwood Tunnel km St Pancras? Code was Y
YU Kingmoor Up Yard km Euston
YW Camden Road Central Junction-Channel Tunnel Rail Link connection km Camden Road Central Junction
0 Gasworks Tunnel km Kings Cross 'Masts' in tunnel are given distance from datum in km only
1 Copenhagen Tunnel km Kings Cross 'Masts' in tunnel are given distance from datum in km only
no prefix Woodhead route miles Manchester Believed that route never had a prefix code, though masts were still numbered according to distance (though see MS). Former DC system, now closed
no prefix Derby works test track

New numbering system km and decimal

Mainly, but not exclusively, Western Region use.

Code Area Datum Note
ABD Abercynon-Aberdare line Queen Street North Junction Early design drawings show this applying through to the terminus, even though the Engineers' Line Reference changes en route (including MOU, ALK and VON); later changed to run to 31.138km. Mile posts count from Bute Road
BHL Reading Oxford Road Junction-Newbury Paddington Electrified to 86.133km
BKE Reading Westbury Line Junction-Basingstoke Paddington Electrified to 61.288km at Reading end only
BLL Bristol Loop Line (Feeder Bridge Junction-Dr Days Junction) Paddington
BSW Bristol East Junction-Severn Tunnel Junction Paddington
CAM Cardiff-Merthyr line Queen Street North Junction Wiring is discontinuous. Mile posts count from Bute Road
CCS Cardiff Canton depot Cardiff Central Wired from 0.057km to 0.357km
DCL Didcot Chester Line Junction-Oxford Paddington When complete, electrification will end around 64 mile post
DEC Didcot East Curve (Didcot East Junction-Didcot North Junction) Paddington Only east end of down line electrified
DWC Didcot West Curve (Foxhall Junction-Didcot West Curve Junction) Paddington
FEC Stoke Gifford Junction No 1-Filton No 1 Junction Paddington
GSM1 Kettering-Corby St Pancras
HEN Henley on Thames branch Paddington
HNL Hereford and Newport line Paddington Only south end electrified. OLE distance counts back from junction; HNL track mileage counts from Rotherwas Junction (near Hereford)
LTN Liverpool Street-Norwich Norwich Anchor mast by Norwich Victoria sidings numbered LTN 1 353
MLN Great Western Main Line Paddington Originally Stockley Junction with J to 56km (near Reading), and c60.5km to Bristol Temple Meads (gap was RW). From August 2017 MLN throughout from Stockley but only wired to 134.560km. Many masts also label nearest track as a suffix. Near Didcot, some initially carried UGL as the prefix in error (corrected by 2020); at Maidenhead some carry MLN1
MLN First few masts of Marlow branch Paddington
MLN1 At least two masts at Maidenhead Paddington
MOA Mountain Ash area Queen Street North Junction Down line only; up line is ABD. Mile posts count from Bute Road
PAC Patchway Curve Patchway Junction No 1 Electrified at Patchway end only
RAD Radyr Branch Cardiff Central (presumed) Electrified north of 1m 39ch only
RFR Reading Feeder Relief line junction with MLN
RTD Reading Traincare Depot Paddington
RWC Reading West Curve Reading West Junction
SPC1 Bedford-Bedford 50 mile post St Pancras
SPC2 Bedford 50 mile post-Wellingborough St Pancras See also SPC2 where registration plates give km and sequence number, not km and decimal
SPC3 Wellingborough to Wigston St Pancras
SWB Wootton Bassett Junction-Patchway Junction No 2 Paddington
SWB First few masts on Stoke Gifford-Hallen Marsh line Paddington
SWM Swindon Junction-Cardiff Central via Gloucester Paddington Only wired to 125.082km and higher than 198.313km
THT Pontypridd-Treherbert line Queen Street North Junction Wiring is discontinuous. Mile posts count from Bute Road
TWD Taffs Well depot sidings 1-9 start of sidings
UGL Up Goods Line Paddington Many masts that should have been MLN near Didcot carried UGL, one had both MLN (with number) and UGL (with number); corrected by 2020
VON Cwmbach-Aberdare line Queen Street North Junction Wired 31.174km to 36.816km only; early design drawings gave this as continuation of ABD. Mile posts count from Taff Vale Extension Junction
WIN Windsor & Eton Central branch Paddington Wired at Slough end only
WYM Wymington deviation St Pancras
YAT Yate branch Paddington Only wired from 171.420km to Westerleigh Junction. OLE distance counts back from junction; YAT track mileage counts from Derby

Codes not certain confirmation is welcome

Code Area Note
DP Landor Street Junction-Proof House Junction Short section at Proof House end wired? Not seen on site
HP St Andrews Junction-Proof House Junction Short spur at the Proof House end? Not seen on site

Suspicious data

This data comes from an unverified source, and should be treated with caution. If you know of the veracity of these codes, please contact the editor.

Code Area Note
BD Chelmsford Royal Mail Terminal One source states that the remains of the link to this terminal uses B, another source suggests the terminal itself had BD. Official records have BCY, with no evidence for BD
H Paddington-High Wycombe Code allocated to Marylebone lines, see H above. allocated, not used?
LG Bridge Street Junction-Gourock Thought to have ben allocated, but duplicated in L above
TH Woodgrange Park Junction-start of line-Gospel Oak Reported, but duplicated in TB above
WB Gospel Oak-Woodgrange Park Reported allocated, probably not used: small section of line at Gospel Oak wired using WG masts
WM Wanton Watts Junction-Millerhill Possibly allocated, but duplicated in EW above

An odd one to complete the record

Code Area Numbering Note
XX Ripple Lane area goods lines Numbered from XX01 to XX07, unrelated to distance Reported, but taken to mean 'fill in details later' and published in official documentation in error, though possibly a temporary code

LBSC/Southern Railway overhead system

The London, Brighton & South Coast Railway chose a DC overhead system to electrify its routes. On merging into the Southern Railway this was replaced with the third rail system still in use today. It is believed that the LBSC did not number its masts at all. The overhead electrified routes were:

Codes not known

Please contact the editor if you can supply missing data.