Signal box prefix codes

A (hopefully) comprehensive listing

'Boxes beginning G

Last update 23 October 2019

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Code Signal Box Note ELR Mileage Opened Closed Control to
G Gaer Temporary panel SWM2 159m 34ch 27 November 1961 9 December 1962 Newport (N)
GN Gaerwen Formerly named Gaerwen No 1.  At least two distant signals CNH3 245m 9ch 1882    
  Gaerwen No 1 See Gaerwen
GC Gainsborough Central Closed, reopened c19 January 1994 MAC3 74m 30ch 1885    
LR Gainsborough Lea Road Burnt down 11 February 2009, some functions taken over by Gainsborough Trent Junction (TJ) 15 February 2009 SPD3 98m 3ch 18 November 1895 4 January 2014 Lincoln Control Centre (LG)
TJ Gainsborough Trent Junction   MAC3 73m 24ch 11 October 1964
(delayed from 10 June 2013)
Lincoln Control Centre (LG) (planned)
G Galashiels Code used from 1937 ETC 33m 48ch 10 January 1937 27 April 1969 Line closed, controlled by Edinburgh (EMB) on reopening
G Garden Street Code possibly not carried MAC3 109m 27ch 1881 26 September 1993 Pasture Street (P)
G Garforth   HUL4 12m 73ch   10 November 1984 Peckfield (P)
D Down line automatic signals
U Up line automatic signals
GD Garngad   SGN 1m 25ch 9 April 2011 25 February 1968 Yoker (YS)
  Garnqueen North Junction   SCM3 97m 5ch c1890 1 May 1999 Cowlairs [new] (CN)
G Garsdale   SAC 256m 55ch 1910    
  Garston Church Road   SCR 24m 0ch 1969 13 June 1993 Speke Junction (SE)
GJ Garston Junction Destroyed by fire 7 July 2003 SCR 23m 47ch 1908 10 April 2006 Speke Junction (SE)
  Gartcosh   GHE 97m 6ch 12 May 1899 1 May 1999 Cowlairs [new] (CN)
GS Gartsherrie South Junction   SCM3 95m 64ch 20 December 1903 1 May 1999 Motherwell (MG)
GW Gascoigne Wood   MGW 6m 27ch 1908    
B Gascoigne Wood down sidings Discharge bunker signals
(Also had draw-ahead signals in colliery sidings lettered A to E (sometimes referred to as SA to SE), with no number)
C Calling on signals
GF Gas Factory Junction   FSS1 2m 52ch 1886 12 June 1961 Upminster [new] (UR)
G Gateshead   PLG2 0m 5ch 9 December 1962 12 April 1991 Tyneside (T)
D Down direction automatic signals
R Banner repeater signals
U Up direction automatic signals
  Gatwick See Gatwick Airport
CM Gatwick Airport Named Gatwick to c1 June 1936 then Gatwick Racecourse to 25 May 1958 VTB3 26m 50ch 1907 26 April 1978 Three Bridges (CL)
CA Automatic signals
  Gatwick Racecourse See Gatwick Airport
G Geneva   DSN1 c1m 16ch   13 May 1972 Darlington (D)
GC Gerrards Cross Named Gerrards Cross West to 11 November 1923.  Code used by 8 February 1953 NAJ2 7m 33ch 1905 11 August 1990 Marylebone [new] (ME)
  Gerrards Cross West See Gerrards Cross
GH Gibbet Hill   LSC2     December 1972 Coventry (CY)
GP Gidea Park   LTN1 13m 63ch 1931 23 August 1997 Liverpool Street [new] (L)
DL Down local line automatic signals
DT Down through line automatic signals
UL Up local line automatic signals
UT Up through line automatic signals
  Gidea Park EMU Sidings   LTN1 13m 75ch 7 December 1997 5 February 2018 Liverpool Street [new] (L)?
G Gilberdyke Junction   HUL1 17m 7ch 1903 23 November 2018 (last train);
26 November 2018 (official)
(delayed from 3 April 2018)
York Rail Operating Centre (GH/SG/TG)
GM Gillingham [Dorset] Downgraded to ground frame 27 February 2012: line controlled by Basingstoke Signalling Control Centre (SE) BAE2 105m 23ch 28 April 1957    
GH Unclear whether code used
ES Gillingham A [Kent]   VIR 35m 78ch 6 May 1913
(inspection date)
21 January 1973 Gillingham [Kent] (ET)
  Gillingham B [Kent] See Gillingham [Kent]
ET Gillingham [Kent] Named Gillingham B to 21 January 1973 VIR 36m 15ch 1913 29 March 2016
(delayed from 3 April 2015)
East Kent Signalling Centre (EK)
A Automatic signals
CFC Gipsy Hill Code used from 2 April 1969.  Three signals only BBJ 7m 71ch 1881 13 July 1969 Victoria Signalling Centre (VC)
GV Girvan Named Girvan No 2 to 11 November 1973.  Code used from 2002 STR2 0m 18ch 26 March 1893    
  Girvan No 2 See Girvan
  Glaisdale   MBW2 c26m 50ch 1902 20 August 1989 Nunthorpe (N)
G Glasgow Central Code used from 1961 AYR1 0m 2ch 2 January 1961 27 December 2008 West Of Scotland Signalling Centre (G/GG/GS)
GR Banner repeater signals WCM2 101m 54ch
T G Some shunt signals: "T" indicates telephone present (see this sketch)
  Glasshoughton Colliery (Had draw-ahead signals in colliery sidings lettered A to C, with no number)          
GC Glasshouse Crossing   PED2 6m 48ch   20 July 1981 Barnsley (BY)
GE Glazebrook East   MAJ 24m 60ch 1961    
G Glencraig Junction   CWH3 29m 29ch 21 April 1896 10 May 1981 Edinburgh (ET)
GN Glendon North Junction   SPC3 74m 77ch 8 May 1904 5 December 1987 Leicester (LR)
GW Glenwhilly Code used from 2002 STR2 20m 70ch 1905    
G Gloucester   BAG2 92m 69ch 25 May 1968 (unknown date) (in part) West Midlands Signalling Centre (BA) (in part)
DC Down Charfield line automatic signals
DG Down goods line automatic signals
DK Down Kemble line automatic signals
DM Down main line automatic signals
GL Signals controlling crossings supervised by Lydney gate box
GP Signals controlling crossings supervised by Pirton gate box.  Code used by 1986
GU Up direction signals on down main/down Charfield lines
UA Up avoiding line automatic signals
UC Up Charfield line automatic signals
UK Up Kemble line automatic signals
UM Up main line automatic signals
ES Gloucester Engine Shed Junction   CHL 92m 30ch 22 February 1942 26 May 1968 Gloucester (G)
CY Gloucester Road Junction   VTB1 9m 59ch 21 March 1954 7 April 1984 Three Bridges [new] (T)
GN Gobowen North   WSJ2 189m 57ch 1884    
GE Godley East Junction   HAJ 8m 75ch December 1906 10 October 1971 Godley Junction (GJ)/
Mottram No 1 (M1)
GJ Godley Junction   HAJ 8m 31ch by 1916 7 December 1984 Dinting (DG)
G Godnow Bridge Gate box: line controlled by Doncaster (D).  Believed code not carried DOW 14m 8ch 1886 15 August 2000 Godnow Bridge [new] (G)
G Godnow Bridge [new] Gate box: line controlled by Doncaster (D).  Believed code not carried DOW 14m 8ch 15 August 2000    
GD Godstone   RTT 28m 14ch 1893 31 May 1986 Three Bridges [new] (T)
(Retained as a ground frame)
GS Ground frame code
GS Golborne Station   CGJ5 c1m 40ch   30 September 1972 Warrington (WN)
GM Gomshall Code used on one signal for 11 days in 1980 whilst control passed to Shalford (WY) and Betchworth (BW) RSJ 35m 17ch 26 October 1941 6 November 1980 Shalford (WY)/
Betchworth (BW)
G Goodmayes   LTN1 9m 36ch 26 September 1949 29 March 1997 Liverpool Street [new] (L)
DE Down electric line automatic signals
DM Down main line automatic signals
UE Up electric line automatic signals
G Goole Named Boothferry Road to 19 January 1975 TJG2 6m 51ch 1909    
BR Code when named Boothferry Road
D Down line automatic signals
R Shunt signals
E Goole Engine Shed   WAG1 73m 52ch   c25 May 1980 Goole Engine Shed [temporary] (E)
WAG2 0m 64ch
WAG3 73m 52ch
E Goole Engine Shed [temporary] Temporary 'box on opposite side of line to previous, damaged, one WAG1 73m 52ch c25 May 1980 19 October 1980 Goole (G)
WAG2 0m 64ch
WAG3 73m 52ch
GB Goole Swing Bridge Britain's first panel 'box (1933), predating Thirsk.  Temporary closure 2 October 2010 to 13 November 2010 TJG2 5m 8ch August 1869    
D Down direction automatic signals
U Up direction automatic signals
G Goonbarrow Junction   NEW 287m 40ch 1909    
G Goose Hill Junction   MVN2 50m 31ch   2 October 1988 Wakefield Kirkgate (K)
GJ Code reported probably in error TJC3 184m 56ch
G Gordon Hill   HDB 9m 55ch 4 April 1910 4 July 1976 Kings Cross (K)
GS Goring & Streatley Code used by 1953 MLN1 44m 47ch January 1892 9 May 1965 Reading (R)
GG Goring By Sea   BLI1 13m 10ch 1900 25 June 1988 Lancing (LG)
G Gorgie Junction   SUB2 0m 49ch 14 December 1897 15 December 1975 Haymarket [temporary panel] (EH)
G Gorton Junction   HAJ 2m 43ch c. July 1906 6 May 1984 Ashburys (AS)
GO Gosberton   SPD1 49m 13ch 6 March 1882 19 March 2012 Gosberton [new] (SL)
SL Gosberton [new] Spalding to Lincoln section SPD1 49m 26ch 19 March 2012 11 August 2014
(delayed from 30 December 2013)
Lincoln Control Centre (SL)
GO Gospel Oak   BOK2 1m 12ch 18 August 1985 27 February 2011 Upminster [new] (NL)
G Goswick Code used from 10 April 1960 ECM7 60m 67ch   28 March 1982
(delayed from 15 March 1981)
Tweedmouth (T)
D Down direction automatic signals
U Up direction automatic signals
GK Gourock Named Gourock No 2 to 14 March 1966 GOU2 c126m 20ch 31 May 1889 22 September 1985 Paisley [new] (PU)
  Gourock No 2 See Gourock
G Goxhill   BAR 104m 50ch 1910    
- Grain Crossing Gate box: line controlled by Ashford IECC (NK) HTG 38m 23ch 11 September 1882    
GS Grand Sluice Downgraded to gate box: line controlled by Boston West Street Junction (WS) GRS3 107m 41ch November 1891 9 November 1985 Boston West Street Junction (WS)
GC Grange Court   GCT 121m 41ch 17 April 1935 2 June 1969 Gloucester (G)
GE Grange Junction   CMD2 18m 26ch 26 February 1966 2 March 2002 (last train);
17 May 2002 (official)
Stoke on Trent Signalling Centre (SOT)
BP Grangemouth BP Terminal   GMH c3m 75ch 1970    
GH Grangemouth Junction Code used from 1979 PMT 23m 71ch c1899 18 August 1997 Grangemouth Junction [new] (GH)
GH Grangemouth Junction [new]   PMT 23m 75ch 18 August 1997 27 December 2017 Edinburgh (ECL)
GS Grange Over Sands Code used from 2008 CBC1 9m 31ch 1956    
R Distant signals
G Grangetown Code used by 1973 DSN2 18m 65ch 30 May 1954    
D Down line automatic signals
R Distant signals
RR Outer distant signals
GS Grangetown Ground Frame Code used by 24 October 1978 BRY 0m 69ch     Sidings closed
G Grantham Named Grantham Yard to 20 February 1972 ECM1 105m 30ch 19 January 1874 3 February 1980 Doncaster (D)
GN Grantham North   ECM1 105m 48ch 15 May 1881 20 February 1972 Grantham (G)
D Down line automatic signals
R Repeater signals
U Up line automatic signals
GS Grantham South   ECM1 105m 7ch 19 January 1874 20 February 1972 Grantham (G)
  Grantham Yard See Grantham
RU Grantshouse Distant to up line automatic signals ECM8 41m 23ch 7 April 1918 20 February 1978 Edinburgh (EG)
U Up line automatic signals
EZ Graveney Crossing   VIR 54m 78ch by 1887 2 November 1972 Faversham (EY)/
Margate (GE)
GG Grayrigg Code used from 15 April 1973 CGJ7 c26m 26ch   28 April 1973 Carlisle (CE)
G Grays Formerly Grays East? TLL 19m 77ch 1900? 8 April 1996 Upminster [new] (UR)
GB Great Barr   PBJ c7m 54ch ?   Walsall (WL)
  Great Bentley Downgraded to gate box 21 December 1958: line controlled by Thorpe-le-Soken (T) COC 60m 62ch 1889 4 May 2009 Colchester [new] (CO)
CH Great Chesterford Downgraded to ground frame?  If so, final closure 14 December 1988 BGK 45m 59ch 1881 11 December 1983 Cambridge (CA)
D Down direction automatic signals
GC Great Coates No 1   MWN 108m 34ch 1909    
GM Greatham Code used from 1 November 2004 LEN3 67m 27ch 1889    
G Code used by 1975
A Great Missenden Automatic signals MCJ2 29m 0ch 1 September 1892 23 April 1990 Marylebone [new] (ME)
R Repeater signals
- Great Rocks Junction   CNB1 163m 2ch 1923    
GS Greaves Sidings Code used by 8 November 1953 DCL 99m 13ch 3 February 1918 ? Fenny Compton (FC)
GK Greenbank   CDM2 22m 21ch 21 December 1975    
G Greenfield Junction   MVL3 12m 46ch 1888 5 April 1999 Stalybridge (SE)
  Greenfoot Level Crossing   SCM3 97m 59ch before 1910 18 April 1999 Cowlairs [new] (CN)
G Greenford East General code as shown on signalling plans ANL 7m 44ch 1 October 1904    
GE One signal only on signalling plans, but many "on the ground"
DB Down branch line automatic signal
GJ Greenhill Junction Named Greenhill Upper Junction to 8 June 1975.  Code used from 1971 EGM1 17m 28ch 1890s 18 November 1990 Greenhill Junction [new] (GJ)
GU Code used from 1966
GJ Greenhill Junction [new] Retained as emergency panel EGM1 17m 28ch 18 November 1990 27 December 2017 Edinburgh (GJ)
GL Greenhill Lower   SCM3 106m 40ch 1886 9 June 1975 Greenhill Junction (GJ)
  Greenhill Upper Junction See Greenhill Junction
GL Green Lane Crossing   WSJ2 211m 1ch c1925 13 January 1985 Chester PSB (CR)
OW Green Lanes Crossing Downgraded to ground frame 5 May 1968 WPH2 41m 68ch 1879 21 November 1976 Portsmouth (PW)
GL Greenloaning Code used from 2002 SCM4 129m 18ch 2 July 1891    
  Green Oak Goit Gate box: line controlled by Gilberdyke Junction (G) TJG2 1m 42ch   23 November 2018 (last train);
26 November 2018 (official)
(delayed from 3 April 2018)
York Rail Operating Centre (SG)
GW Greenock West   GOU2 c123m 76ch 31 May 1889 12 February 1967 Ladyburn (L)
U Greenwood Up line automatic signals ECM1 10m 10ch April 1876 26 April 1959 Potters Bar [new] (PB)?
HM Greetland Emergency Operating Panel Panel still available for emergency use: dates for regular planned use MVN2 30m 77ch 27 July 2009 7 August 2009 Healey Mills (HM)
G Greetland Junction Named Greetland No 2 to 25 September 1966.  Switched out for many years, restored 3 April 2000 MVN2 30m 77ch 1942 26 July 2009 Greetland Emergency Operating Panel (HM)
R Distant signals
  Greetland Mill   BFB 7m 27ch by 1880 27 November 1966 Bradford Junctions (BJ)
  Greetland No 2 See Greetland Junction
G Greskine   WCM1 45m 25ch   29 April 1973 Motherwell (MC)
GL Gresty Lane Named Gresty Lane No 1 to 28 October 1984.  Demolished 17 January 2016 SYC 0m 33ch 18 December 1898 5 December 2015 Gresty Lane Signalling Centre (GL)
CSG 157m 47ch
GSG 0m 0ch
GLP Gresty Lane Down Sidings Ground Switch Panel Stop boards SYC 0m 61ch 7 December 2015    
GL Code possibly not used (see Gresty Lane Signalling Centre)
  Gresty Lane No 1 See Gresty Lane
GL Gresty Lane Signalling Centre In same building as Crewe Signalling Centre LLI 158m 21ch 7 December 2015    
GA Gretna Junction   WCM1 8m 57ch 10 October 1915 7 July 1973 Carlisle (CE)
GAR Distant signals
GJ Griff Junction   CNN     3 February 1985 Nuneaton (NN)
GD Grindleford   MAS 159m 6ch 1934    
G Code given on 2006 signalling plan
B Grimesthorpe Junction No 2 Temporary code until taken over by Brightside (B) TJC2 c160m 34ch   8 August 1965 Brightside (B)
G Grimethorpe Colliery Panel in shunter's cabin.
(Also had draw-ahead signals in colliery sidings lettered A-E, with no number)
    23 October 1977   Colliery closed
G Gristhorpe Downgraded to gate box 13 March 1983: line controlled by Seamer West (SW) HBS 46m 38ch 1873    
EBF Grove Junction Code used by June 1957 TTH 34m 56ch 15 October 1932 19 April 1986 Tonbridge (PE)
A Automatic signals
Z Grove Park Code used from c1960 XTD 9m 7ch 4 September 1938 3 February 1962 Hither Green (P)
GR Grove Road Downgraded to gate box 22 August 1978: line controlled by Retford (RD) (later Doncaster (D)) ECM1 137m 37ch October 1887 15 March 1998 Doncaster (D)
GC Grovesend Colliery Loop   SDI2 9m 35ch 1913 7 July 1973 Port Talbot (PT)
GB Guide Bridge Named Ashton Junction to 10 December 1984.  Code used from renaming HAJ 5m 4ch 1909 5 December 2011
(delayed from 16 October 2011)
Manchester East Signalling Control Centre (GB)
R Banner repeater signals
A Code to 10 December 1984
GBE Guide Bridge East Junction   HAJ 5m 31ch December 1906 24 November 1984 Guide Bridge (GB)
GN Guide Bridge North Junction   SAJ 0m 22ch January 1907 9 December 1984 Guide Bridge (GB)
WX Guildford [panel]   WPH1 30m 9ch 17 April 1966 30 October 1998 Guildford ASC (GD)
CA Automatic signals
DCA Distant to automatic signals
RWA Repeaters to automatic signals
WA Automatic signals
GD Guildford ASC   WPH1 30m 40ch 30 October 1998    
WY Guildford South   WPH1   July 1886 17 April 1966 Guildford [panel] (WX)
WX Guildford Yard   WPH1 30m 18ch July 1886 17 April 1966 Guildford [panel] (WX)
G Guisborough Junction Burnt out June 1980 DSN2 c15m 23ch   June 1980 Guisborough Junction [temporary] (G)
G Guisborough Junction [temporary]   DSN2 c15m 23ch June 1980 8 May 1982 Middlesbrough (M)
GY Guisley Also called Guisley Station ILK1 205m 22ch 1906 11 July 1994 Leeds (L)
G Earlier code
G Guisley Junction "Shipley Guisley Junction" carried on 'box TJC3 205m 45ch 1901 25 July 1994 Leeds (L)
GJ GUE 3m 41ch
  Guisley Station See Guisley
G Gunhouse Junction   DOW 20m 34ch c21 May 1916 31 March 1973 Scunthorpe (S)
WBM Gunnersbury   SAR2 9m 68ch 1 January 1869 26 March 1980 Richmond (GB)
G Gyfeillon Upper   THT 14m 34ch c1897 16 December 1984 Pontypridd (P)


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