Last update 11 October 2021
Please select a starting letter from the links below:
| ELR | Line name | Mileages | Datum | Notes |
|---|
| CAA | Canal Branch | 0.21 - 1.14 | Carlisle London Road Junction | |
| CAB | Coupar Angus to Blairgowrie Branch | 0.00 - 4.51 | Coupar Angus Junction | |
| CAC | Calderbank Colliery Branch | 0.00 - 1.30 | Calderbank Branch Junction | |
| CAD | Chadderton Goods Branch | Now CDD | ||
| CAD | Cadzow Branch | 0.00 - 1.40 | Cadzow Junction | Cadzow Junction on Hamilton to Motherwell line |
| CAE | Caelliau Branch | 14.50 - 16.15 | Swansea St Thomas Station | |
| CAG | Coventry Avoiding Line | 0.00 - 3.44 | Humber Road Junction | |
| CAH | Cart Harbour Branch | 6.36 - 6.72 | Bridge Street | |
| CAI | Calderbank Ironworks Branch | 0.00 - 0.47 | Calderbank Ironworks Box | |
| CAK | Calderbank Branch | ?? - ?? | Possibly Airdrie to Morningside line, datum Rutherglen East Junction | |
| CAL | Callington Branch | 0.02 - 9.50 | Bere Alston Junction | |
| CAM | Cardiff and Merthyr Line | 0.00 - 24.51 | Cardiff Bute Road | 24.19 - 24.51 formerly MER 5.70 - 6.22 |
| CAN | Carmarthen and Newcastle Emlyn Line | 245.10 - 270.67 | Paddington via Stroud | |
| CAO | Cawood Wistow and Selby Light Railway | 0.00 - 4.48 | Selby Junction | |
| CAP | Caerphilly and Pontypridd Line | 8.36 - 14.48 | Cardiff East Dock | |
| CAR | Cardiff and Rhymney Line | 0.00 - 24.00 | Cardiff East Dock | 23.66 - 24.00 formerly RRZ |
| CAS | Castella Branch (Old Glanmyshyd Branch) | ≈1.75 - ≈3.00 | Ely Valley Junction | Formerly CTZ |
| CAT | Catford Loop | 3.08 - 10.73 | Victoria | |
| CAW | Cricklewood to Acton Wells Line | 5.19 - 8.77 | St Pancras | |
| CAY | Camden Yard | 5.15 - 5.25 | Broad Street | |
| CAZ | Crockherbtown Carriage Sidings | 1.21 - ?? | Cardiff East Dock | Now in CHT |
| CBB | Cambusnethan Branch | 0.00 - 2.27 | Wishaw Central South Junction | |
| CBC | Carnforth Barrow and Carlisle Line | see separate portions | ||
| CBC1 | Carnforth North Junction to Whitehaven | 0.00 - 74.73 | Carnforth North Junction | |
| CBC2 | Whitehaven to Maryport Junction | 0.00 - 12.05 | Whitehaven | |
| CBC3 | Maryport to Carlisle | 0.00 - 27.58 | Maryport Junction | |
| CBD | Cumbernauld Line (Springburn to Garnqueen North Junction) | see separate portions | ||
| CBD1 | Gartcosh Junction to Garnqueen Junction | 0.00 - 1.33 | Gartcosh Junction | |
| CBD2 | Sighthill East Junction to Gartcosh Junction | 97.06 - 103.46 | Carlisle via Ravenscraig No 1 | |
| CBE | Cambridge Goods | 55.28 - 55.54 | Liverpool Street via Clapton | |
| CBH | Cransley Branch | 0.00 - 1.47 | Cransley Branch Junction | |
| CBI | Canal Tunnels | 0.00 - 0.53 | St Pancras Junction/Canal Tunnel Junction | |
| CBL | Camelon Branch | 19.47 - 22.07 | Glasgow Queen Street High Level | |
| CBM | Cannon Street to Borough Market Junction Line | 0.00 - 0.38 | Cannon Street | |
| CBN | Carbean Branch | 290.42 - 290.75 | Paddington via Box, Plymouth Millbay (reverse) and Carbean Junction (reverse) | |
| CBR | Castle Bromwich to Ryecroft (Walsall) Line | see separate portions | ||
| CBR1 | Castle Bromwich Junction to Park Lane Junction | 0.00 - 1.26 | Park Lane Junction | |
| CBR2 | Park Lane Junction to Ryecroft Junction | 36.04 - 47.54 | Derby via Whitacre Junction | |
| CBS | Carbis Branch | 287.43 - 289.13 | Paddington via Box, Plymouth Millbay (reverse) | |
| CBV | (Cardiff) Bute Viaduct Lines | 0.00 - 0.33 | Tyndall Street High Level Junction | |
| CBX | Carmyle and Bridgeton Cross Line | 97.32 - 100.33 | Carlisle | |
| CBY | Canning Town Blackwall Yards | 5.76 - 6.35 | Liverpool Street via Canning Town (reverse) | |
| CBZ | Clutton Branch | 0.00 - 0.63 | Clutton | |
| CCA | Cornbrook Junction to Castlefield Junction | 32.77 - 33.57 | Liverpool Central High Level | |
| CCB | Cotgrave Colliery Branch | see separate portions | ||
| CCB1 | Rectory Junction to Cotgrave Colliery | 0.00 - 1.63 + colliery | Cotgrave Colliery West Junction | |
| CCB2 | Cotgrave Colliery East Curve | 0.00 - 0.25 | Junction with Grantham to Nottingham line | |
| CCC | Cardiff Canton Carriage & DMU Depot | 170.60 - 171.27 | Paddington via Stroud | |
| CCD | Cardiff Canton Locomotive Depot | 170.60 - 171.21 | Paddington via Stroud | |
| CCE | Campbell Road Curve | 3.56 - 4.09 | Broad Street | Or to 4.12 |
| CCF | Cotcastle Fork (Stonehouse - Strathaven) | ?? - ?? | Track never laid | |
| CCG | Croxley Green Branch | see separate portions | ||
| CCG1 | Colne Junction to Croxley Green Junction | 16.39 - 16.58 | Euston | |
| CCG2 | Croxley Green Junction to Croxley Green | 16.58 - 18.09 | Euston | |
| CCH | Cambridge Coldham Lane Junction and Haughley Junction Line | 0.00 - 40.52 | Cambridge Coldham Lane Junction | |
| CCL | Castle Cary and Langport Line | 115.33 - 138.30 | Paddington via Newbury | |
| CCN | Clipstone Colliery Branch | 9.09 - 9.56 | Kirkby South Junction via Mansfield | |
| CCO | Camps Connecting Line | 0.00 - 0.13 | Exchange Junction | |
| CCQ | Chester and Connah's Quay Curve (Dee Marsh) | see separate portions | ||
| CCQ1 | Chester East Junction to Dee Marsh East Junction | 0.00 - 5.61 | Chester East Junction | |
| CCQ2 | Dee Marsh East Junction to Dee Marsh North Junction | 5.61 - 6.10 | Chester East Junction | |
| CCQ3 | Dee Marsh East Junction to Dee Marsh West Junction | 5.61 - 6.18 | Chester East Junction | |
| CCR | Conon to Cromarty Branch | n/a | n/a | Never built |
| CCS | Cardiff Canton - all other sidings not listed elsewhere | 0.19 - 0.66 | Cardiff Central | |
| CCS | Rock Ferry and Cathcart Street Goods Branch (Birkenhead Goods Extension Line) | see separate portions | ||
| CCS1 | Rock Ferry to Birkenhead Woodside | 13.30 - 15.14 | Chester | |
| CCS2 | Green Lane to Cavendish Sidings | 14.06 - 15.42 | Chester | |
| CCS3 | Green Lane Junction to Monks Ferry | 14.14 - 15.05 | Chester | |
| CCS4 | Green Lane Junction to Abbey Street | 14.36 - 14.56 | Chester | |
| CCT | Chorley and Cherry Tree Branch | 22.25 - 29.73 | Manchester Victoria | |
| CCV | Clifton Curve | 0.00 - ≈0.63 | Wetheriggs Junction | |
| CCY | Cadeby Colliery Branch | 0.00 - 0.22 | Branch Junction | |
| CCZ | Liskeard and Caradon Line | 7.29 - 20.75 | Looe Quay | |
| CDB | Craighead Branch | ?? - ?? | Craighead Colliery was served by North British and Caledonian Railways: not known to which this applies | |
| CDC | Perth to Ladybank Line | see separate portions | ||
| CDC1 | Ladybank to Bridge of Earn | 0.00 - 14.10 | Ladybank Junction | |
| CDC2 | Bridge of Earn to Hilton Junction | 44.18 - 45.66 | Edinburgh Waverley via Cowdenbeath New | |
| CDD | Chadderton Goods Branch | 5.35 - 6.25 | Manchester Victoria via Moston | Formerly CAD |
| CDK | Cardiff Docks | see separate portions | ||
| CDK1 | Splott Junction to Roath Dock Road Level Crossing | 4.54 - 5.20 | Roath Branch Junction | |
| CDK2 | Splott Junction to Locks Road | 4.54 - 5.20 | Roath Branch Junction | |
| CDK3 | Compass Road to Longship Road | 5.20 - 6.26 | Roath Branch Junction | |
| CDK4 | Junction Lock Road to Frigate Road | 5.12 - 6.26 | Roath Branch Junction | |
| CDM | Deansgate (Manchester) and Dee Marsh (near Chester) Line | see separate portions | ||
| CDM1 | Castlefield Junction to Altrincham | 0.37 - 8.08 | Manchester Oxford Road | |
| CDM2 | Altrincham to Mickle Trafford | 7.69 - 35.41 | Manchester Central | |
| CDM3 | Mickle Trafford to Chester Northgate | 35.24 - 38.53 | Manchester Central | |
| CDN | Clevedon Branch | 0.00 - 3.45 | Yatton Station | |
| CDO | Chatham Dockyard Branch | Now CYD | ||
| CDS | Chesterford to Six Mile Bottom Branch | 0.00 - ≈9.21 | Chesterford Junction | |
| CDT | City and District Branch | 0.00 - 2.04 | Campbell Road Junction | |
| CDV | Cheadle Deviation Branch | ≈1.33 - ≈3.57 | Cresswell Junction | |
| CDY | Chelmsford Freight Yard | 29.64 - 30.25 | Liverpool Street | |
| CDZ | Common Branch Loop Line | 0.00 - 0.40 | Llantrisant West Junction | |
| CEB | Cardiff East Branch | 0.00 - 0.66 | East Branch Junction | |
| CEC | Carnforth East Curve | 0.04 - 0.25 | Carnforth | |
| CED | Castle Eden Branch | ?? - ?? | ||
| CEF | Crofton East Fork | 0.00 - 0.38 | Crofton East Junction | |
| CEH | Castleton East Junction and Heywood Line | 0.00 - 0.37 | Castleton East Junction | |
| CEJ | Cardiff East Junction | 0.00 - 0.22 | Cardiff East Junction | Formerly 0.22 - 0.44 ex Riverside Junction |
| CEM | Clipstone East Junction to Mansfield Colliery Branch | 6.32 - 11.09 | Kirkby South Junction via Mansfield | |
| CEN | Camelon Branch | 0.00 - 1.16 | Camelon Junction | |
| CER | Colchester Goods | 50.72 - 51.49 | Liverpool Street | |
| CET | Castleford East Branch | 0.00 - 0.27 | Castleford East Junction | |
| CEZ | Cardiff East Branch | Now SWR | ||
| CFB | Cargo Fleet White House Branch | 0.00 - 1.00 | ||
| CFG | Coleford Branch | 0.00 - 5.20 | Wyesham Junction | Formerly 67.75 - 73.15 ex ?? Formerly COL |
| CFH | Church Fenton to Harrogate Line | see separate portions | ||
| CFH1 | Church Fenton to Crimple Junction | 0.00 - 16.42 | Church Fenton North Junction | |
| CFH2 | Crimple Junction to Harrogate | 16.42 - 18.37 | Church Fenton North Junction | Line re-miled at some stage and now LEH3 |
| CFJ | Coalfields Farm Colliery to Coalville Junction Branch | 0.00 - 0.62 | Coalville Junction | |
| CFL | Charnwood Forest Line | 0.00 - 10.30 | Charnwood Forest Junction | |
| CFM | Church Fenton and Micklefield Line | 10.31 - 15.62 | York | |
| CFN | Carfin Branch (Boiler Works - Newarthill Halt - Holytown & Cleland) | 0.00 - 0.35 | Carfin Colliery Box | Caledonian Railway branch to Carfin Colliery No 6 on Wishaw Extension Line |
| CFP | Canonbury to Finsbury Park Curve | 3.12 - 4.33 | Broad Street | |
| CFR | Cardiff Riverside Branch | 0.00 - 1.08 | Cardiff Riverside Branch Junction | Formerly CRS |
| CFS | Coleford Branch | 12.71 - 16.49 | Berkeley Road Junction via Coleford Branch Junction (reverse) | Formerly CSW |
| CFY | Connell Ferry to Ballachulish Line | 0.00 - 27.48 | Connel Ferry West Junction | |
| CFZ | Cwmffrwd Branch | 12.67 - 14.07 | George Street Junction via Golynos Junction (reverse) | |
| CGB | Cockett Goods Branch | 216.74 - 217.38/ 0.00 - 0.44 | Paddington via Stroud/Cockett Junction | |
| CGJ | Carlisle Grand Junction Line (WCML Crewe to Carlisle) | see separate portions | ||
| CGJ1 | Crewe to Weaver Junction | 159.00 - 176.00 | Euston | |
| CGJ2 | Weaver Junction to Warrington | 176.00 - 181.76 | Euston | |
| CGJ3 | Warrington to Winwick Junction | 181.76 - 185.49 | Euston | |
| CGJ4 | Winwick Junction to Golborne Junction | 185.49 - 187.76 | Euston | |
| CGJ5 | Golborne Junction to Preston | 0.53 - 21.57 | Newton-Le-Willows Junction | |
| CGJ6 | Preston to Lancaster | 0.00 - 20.78 | Preston | |
| CGJ7 | Lancaster to Carlisle | 0.00 - 69.09 | Lancaster | |
| CGL | Collyhurst Connection Line No 3 | 1.10 - 1.30 | Manchester Victoria | |
| CGS | Cartside Goods Line (Johnstone) | 0.00 - 0.29 | Cart Junction | |
| CGV | Corngreaves Branch | 0.00 - 0.60 | Cradley Junction | |
| CGW | Carlisle Gas Works Siding | 0.00 - 0.20 | Rome Street Junction | |
| CGZ | Cwmbargoed Branch | 17.32 - 19.60 | Abergavenny Junction | |
| CHA | Chapel Street Branch | ?? - ?? | Southport, or Chapel Street Mineral Siding at Greenock Central?? | |
| CHB | Chesterton Branch | 0.00 - 1.51 | junction with TLK | |
| CHC | Chapelhall Colliery Branch | 0.00 - 0.27 | Calderbank Station | Between Calderbank and Chapelhall on Caledonian Railway Airdrie to Morningside line |
| CHD | Chard Branch (GWR) | 0.00 - 13.08 | Creech Junction | |
| CHE | Cheadle to Cresswell Junction | 0.00 - 3.71 | Cresswell Junction | |
| CHE | Cheltenham Branch | 2.70 - 7.03 | Gloucester | 5.74 - 7.03 now CTM; 2.70 - 5.74 now 90.03 - 86.74 ex Derby in BAG2 |
| CHF | Coppermill Junction to Hall Farm Junction Line | 0.00 - 0.23 | Coppermill Junction | |
| CHH | Chickenley Heath Branch | 180.03 - 183.12 | Kings Cross | |
| CHI | Chilton Branch | ?? - ?? | ||
| CHI1 | Chilton Colliery Branch | ?? - ?? | ||
| CHJ | Carterhouse Junction to West Deviation Junction Line | 16.28 - 17.48 | Skelton Junction | |
| CHL | Cheltenham Loop/Gloucester Old Avoiding Line | 92.21 - 93.09 | Derby | |
| CHM | Channelsea North Junction to High Meads Junction | 0.00 - 0.15 | Channelsea North Junction | |
| CHN | Crockherbtown Loop | Now CHT | ||
| CHN | Castle Hills South Junction to West Junction Curve | 0.00 - 0.16 | Castle Hills South Junction | |
| CHP | Cromford and High Peak Line | see separate portions | ||
| CHP1 | No 1, Hindlow to Cromford | 4.70 - 24.06 | Buxton No 1 Junction | |
| CHP2 | No 2, Hindlow to Whaley Bridge | 0.00 - ≈10.36 | Hindlow | |
| CHQ | Huyton Quarry Junction to Cronton Colliery Branch | 0.00 - 0.76 | Huyton Quarry Junction | |
| CHR | Chesterfield and Rotherham Line | 146.59 - 162.24 | St Pancras via Leicester, Toton and Barrow Hill | |
| CHS | Crigglestone Junction and Horbury Junction Link Line | 0.00 - 1.53 | Horbury Junction | |
| CHT | Crockherbtown Loop | 1.15 - 1.34 | Cardiff East Dock | Formerly CHN |
| CHW | Chester and Warrington Line | see separate portions | ||
| CHW1 | Chester East Junction to Walton Old Junction | 0.27 - 17.23 | Chester | |
| CHW2 | Walton Old Junction to Warrington | 17.23 - 17.76 | Chester | |
| CHY | Cinder Hill Colliery Branch | 128.65 - 128.67 | St Pancras via Corby | |
| CHZ | Coalpit Heath Colliery Branch | 0.00 - 1.02 | Coalpit Heath Branch Junction | |
| CIB | Cinderford Branch | 5.05 - 8.05 | Forest of Dean Junction | Line to ≈9.60 never opened |
| CIL | Chester Independent Lines | 157.64 - 158.24 | Euston | |
| CIR | Cirencester Branch | 90.73 - 95.16 | Paddington | |
| CIW | Clyde Ironworks Branch | 0.00 - 0.13 | Clyde Junction | |
| CIZ | Caedu Incline | 5.18 - 5.66 | Tondu Middle Junction | Line re-miled: Datum = Copper Works Junction after 1950 |
| CJA | Copyhold Junction and Ardingly Line | see separate portions | ||
| CJA1 | Copyhold Junction to Haywards Heath | 36.34 - 37.00 | London Bridge via Redhill | |
| CJA2 | Copyhold to Ardingly | 0.00 - 1.14 | Copyhold Junction | |
| CJA3 | Ardingly to Horsted Keynes | 1.14 - 3.21 | Copyhold Junction | |
| CJB | Chard Junction Branch | 0.00 - 2.79 | Chard Junction | |
| CJC | Clapton Junction and Chingford Branch | 4.38 - 10.33 | Liverpool Street | |
| CJD | Challoch Junction to Dumfries Line | 0.00 - 66.29 | Dumfries | Or from 3.01 if does not include MAX |
| CJL | Clapham Junction to Latchmere No. 2 Junction Line | 0.37 - 0.68 | Kensington sidings buffer stops | |
| CJM | Camps Branch (LMS) | 0.00 - 1.28 | Camps Junction | |
| CJN | Camps Branch (LNE) | 0.00 - 3.51 | Camps Branch Junction | |
| CJS | Carcroft Junction to Stainforth Junction Line | 160.08 - 166.70 | Kings Cross via Carcroft | |
| CKC | Cannock Chase Line | 0.00 - 5.42 | Hednesford | |
| CKL | Calvert Road Junction to Latchmere No. 1 Junction Line | 1.67 - 2.51 | Victoria | |
| CKN | Cleckheaton Branch | 0.00 - 8.48 | junction with MRB | |
| CKP | Cockermouth, Keswick and Penrith Line | 0.00 - 30.59 | Cockermouth junction with CWN | |
| CKS | Cricklewood Sidings | see separate portions | ||
| CKS1 | Cricklewood Sidings | 5.08 - 6.21 | St Pancras | |
| CKS2 | Cricklewood Sidings | 5.29 - 5.62 | St Pancras | |
| CKT | Craiglockhart Loop | 0.00 - 0.48 | Craiglockhart Junction | |
| CLA | Ashford Chart Leacon Depot | see separate portions | ||
| CLA1 | Not allocated | n/a | n/a | |
| CLA2 | Not allocated | n/a | n/a | |
| CLA3 | Not allocated | n/a | n/a | |
| CLA4 | Not allocated | n/a | n/a | |
| CLA5 | Not allocated | n/a | n/a | |
| CLA6 | Not allocated | n/a | n/a | |
| CLA7 | Not allocated | n/a | n/a | |
| CLA8 | Roads 1 to 9 | 54.72 - 55.68 | Charing Cross via Chelsfield | |
| CLA9 | Roads 10 to 18 | 54.76 - 55.21 | Charing Cross via Chelsfield | |
| CLB | Crianlarich Lower Branch | 29.27 - 30.23 | Callander | |
| CLC | Warrington Avoiding Line | 17.20 - 19.49 | Manchester Central | Cheshire Lines Committee |
| CLD | Caldon Low Branch | 0.00 - 0.51 | Caldon (or Cauldon) Junction | |
| CLE | Clee Hill Branch | 0.00 - 6.01 | Clee Hill Junction | |
| CLF | Clifton and Kearsley Branch (Dixon Fold to Kearsley) | 0.00 - 3.40 | Patricroft Junction | |
| CLH | Cliff House Branch | see separate portions | ||
| CLH1 | Main Branch | 0.00 - 1.06 | Cliff House Junction | |
| CLH2 | Scrap Yard Branch | 0.42 - 2.00 | Cliff House Junction via junction with CLH1 (reverse) | |
| CLI | Cleveland Steelworks Branch | 17.50 - 18.19 | Darlington | |
| CLJ | Clapham Junction Sidings | see separate portions | ||
| CLJ1 | Sidings 34 to 49 | 3.65 - 4.26 | Waterloo | = CLJ9?? |
| CLJ2 | Not allocated | n/a | n/a | |
| CLJ3 | Not allocated | n/a | n/a | |
| CLJ4 | Not allocated | n/a | n/a | |
| CLJ5 | Not allocated | n/a | n/a | |
| CLJ6 | Not allocated | n/a | n/a | |
| CLJ7 | Not allocated | n/a | n/a | |
| CLJ8 | Sidings 1 to 33 | 3.68 - 4.12 | Waterloo | |
| CLJ9 | Sidings 34 to 49 | 3.68 - 4.26 | Waterloo | |
| CLK | Carluke Branch | 0.00 - 3.07 | Castlehill Junction | |
| CLL | Cardiff Leckwith Loop | 0.00 - 0.26 | Leckwith Junction North | |
| CLN | Chesterfield to Lincoln Line | see separate portions | ||
| CLN1 | Chesterfield to Shirebrook North | 0.00 - 10.19 | Chesterfield Market Place | |
| CLN2 | ?? | 5.00 - 7.00 ?? | Chesterfield Market Place | Covers footbridge no 36 on line to WH Davis siding |
| CLN3 | High Marnham Junction - Pyewipe Junction | 28.01 - 37.62 | Chesterfield Market Place | |
| CLO | Chesterfield Loop | 0.00 - 9.47 | Staveley Central | |
| CLP | Clarkston Loop | 0.00 - 0.32 | Clarkston East Junction | No regular traffic, lifted 1st world war |
| CLS | Caernarvon to Llanberis Line | 0.00 - 9.00 | Caernarvon Junction | |
| CLU | Congleton Lower Junction to Congleton Upper Junction | 12.22 - 12.54 | original Stoke Junction | |
| CLV | Liverpool Central High Level Station to link with CLC Deviation | 0.00 - 0.28 | Liverpool Central High Level | |
| CLW | South Bank Junction to Clay Lane Works Branch | 17.15 - 17.52 | Darlington | |
| CLY | Clydesdale Line (Shields Junction to Larkfield Junction - Glasgow Central) | 100.60 - 102.18 | Carlisle | |
| CLZ | Clandown Branch | 10.17 - 10.61 | Bath Junction | |
| CMB | Cwmbran Branch/Llantarnam (or Passenger) Branch | 0.00 - 0.67 | Llantarnam Junction | |
| CMC | Cwmcarn Branch | 0.26 - 1.73 | Halls Road Junction | |
| CMD | Colwich Junction to Macclesfield Line | see separate portions | ||
| CMD1 | Macclesfield to Harecastle | 0.00 - 16.00 | Macclesfield Hibel Road | |
| CMD2 | Harecastle to Colwich | 15.65 - 38.61 | Macclesfield Hibel Road | |
| CMD3 | Harecastle Tunnel Line | 14.01 - 15.65 | Macclesfield Hibel Road | |
| CME | Campsie Branch | 6.16 - 22.42 | Glasgow Queen Street High Level | |
| CMF | Cwmffrwdoer Branch | 10.39 - 11.65 | George Street Junction | |
| CMG | Cwmgorse Branch | 0.00 - 2.73 | Abernant Junction | Line onwards to Pontardawe never completed |
| CMH | Canons Marsh Branch | 0.00 - 1.07 | Ashton Swing Bridge Junction | Formerly BAS |
| CMI | Cleland and Morningside Branch | 1.72 - 7.03 | Mossend North Junction | |
| CMJ | West Croydon to Mitcham Junction Line | 3.08 - 6.12 | Wimbledon | |
| CML | Cambridge Fordham and Mildenhall Line | 1.46 - 20.62 | Cambridge | |
| CMM | Cwmmawr Branch/Burry Port & Gwendraeth Valley Branch | 0.00 - 12.52 | Burry Port Station | |
| CMN | Cwmnantddu Branch | 9.78 - 12.03 | George Street Junction | |
| CMO | Chester to Mold Line | 0.00 - 9.57 | Mold Junction | |
| CMP | Crewe and Manchester Piccadilly Line | see separate portions | ||
| CMP1 | Crewe North Junction to Edgeley Junction No 1 | 158.18 - 182.38 | Euston | |
| CMP2 | Edgeley Junction No 1 to Manchester Piccadilly | 182.38 - 188.70 | Euston | |
| CMR | Cymmer Junction Loop | Now CYM | ||
| CMR | Clifton Mill to Rugby Loop | 0.00 - 0.41 | Clifton Mill Junction | |
| CMS | Carmuirs South Curve | 0.00 - 0.40 | Carmuirs West Junction | |
| CMT | Cwmtillery Branch | 16.05 - 17.00 | Courtybella | |
| CMY | Clifton May Bank Branch | 142.57 - 143.21 | Paddington via Melksham | |
| CMZ | Camerton Branch | 0.00 - 11.32 | Limpley Stoke Junction | Formed from Camerton Branch (0.00 - 3.24 ex Camerton Branch Junction, now 8.08 - 11.32) and Limpley Stoke and Camerton Branch (0.00 - 8.08) |
| CNB | Chinley North Junction and Buxton Branch | see separate portions | ||
| CNB1 | Peak Forest Junction to Chinley North Junction | 161.05 - 168.39 | St Pancras | |
| CNB2 | Peak Forest Junction to Buxton Junction | 0.00 - 0.30 | Peak Forest Junction | |
| CNB3 | Millers Dale Junction to Buxton Curve Junction | 160.44 - 164.32 | St Pancras | |
| CNB4 | Buxton Curve Junction to Buxton Sidings | 164.32 - 164.73 | St Pancras | |
| CNB5 | Buxton Curve Junction to Buxton Midland Station | 164.32 - 164.55 | St Pancras | |
| CNC | Cathcart North Curve | 0.00 - 0.45 | Cathcart North Junction | |
| CND | Cardonald and Deanside Branch | see separate portions | ||
| CND1 | Cardonald Junction to Cardonald North Junction | 0.00 - 0.36 | Cardonald Junction | |
| CND2 | Cardonald North Junction to Deanside | 0.36 - 1.62 | Cardonald Junction | |
| CNE | Calne Branch | 0.00 - 5.25 | Calne Branch Junction | |
| CNG | Croes Newydd Junction and Gatewen Branch | 0.00 - 1.66 | Croes Newydd Junction | |
| CNH | Crewe North and Holyhead Line | see separate portions | ||
| CNH1 | Crewe North Junction to Chester East Junction | 158.18 - 178.67 | Euston | |
| CNH2 | Chester East Junction to Chester South Junction | 178.67 - 179.56 | Euston | |
| CNH3 | Chester South Junction to Holyhead | 179.56 - 264.43 | Euston | |
| CNH4 | Not allocated | n/a | n/a | |
| CNH5 | Not allocated | n/a | n/a | |
| CNH6 | Not allocated | n/a | n/a | |
| CNH7 | Not allocated | n/a | n/a | |
| CNH8 | Reserved for future Chester remodelling | 178.67 - 179.48 | Euston | |
| CNH9 | Reserved for future Chester remodelling | ?? - ?? | Euston | |
| CNL | Cornwall Loop | Now CNP | ||
| CNL | (Paisley) Canal Line | 1.06 - 9.11 | Port Eglinton Junction | |
| CNN | Coventry and Nuneaton Line | 0.00 - 9.53 | Coventry North Junction | |
| CNP | Cornwall Loop | 246.08 - 246.29 | Paddington via Box | Formerly CNL |
| CNS | Carpenters Road North Junction to South Junction | 0.70 - 1.12 | Victoria Park Junction | |
| CNT | Consett Branch | 0.00 - 13.57 | Ouston Junction | |
| CNV | Caernarvonshire Line | 0.00 - 18.40 | Caernavon Junction | |
| CNW | Carmarthen West Loop | 0.00 - 0.19 | Carmarthen Bridge Junction | |
| CNX | Clifton Extension Line | 2.03 - 9.29 | Bristol Temple Meads | Originally 0.00 - 3.56 from Narroways Hill Junction. 5.59 - 9.29 formerly HAA |
| CNZ | Coegnant Branch/Duffryn Branch | 9.16 - 9.63 | Bridgend | |
| COA | Coalport Branch | 0.00 - ≈8.02 | Hadley Junction | |
| COB | Cardiff and Ogmore Branch | 0.00 - 8.21 | Llanharan Junction | |
| COC | Colchester and Clacton Line | 51.65 - 69.56 | Liverpool Street | |
| COD | Corton Wood Colliery Branch | 0.00 - 2.50 | Elsecar Junction | |
| COE | Coxhoe Branch | 0.00 - 2.17 | Coxhoe Junction | |
| COG | College Goods Branch | 0.00 - 0.29 | High Street | |
| COH | Corkerhill (Wilsons) Branch | 0.00 - 0.06 | Corkerhill siding | Near Corkerhill shed |
| COI | Cowdenbeath Old to Invertiel Junction (Auchtertool Branch) | 0.00 - 4.17 | Invertiel Junction | |
| COJ | Cowdenbeath Old Branch | 21.37 - 23.50 | Edinburgh Waverley | |
| COL | Coleford Branch (GW) | Now CFG | ||
| COL | Manchester and Ordsall Lane Junction Branch | 188.48 - 190.28 | Euston | |
| COM | Comedie Branch | ?? - ?? | ||
| CON | Clydeport Containerbase Terminal Branch | see separate portions | ||
| CON1 | Garvel Dock Junction to Containerbase Junction | 0.00 - 0.19 | Garvel Dock Junction | |
| CON2 | Cartsburn Junction to Garvel Dock Junction | 22.59 - 23.17 | Port Eglinton Junction | |
| CON3 | Cartsburn Junction to Clydeport | 22.59 - 24.42 | Port Eglinton Junction | |
| COR | Corkickle to Rowrah Line | 0.00 - 6.77 - ?? | ||
| COR | Corris Railway | see separate portions | ||
| COR1 | Corris Railway (main route) | 0.00 - 8.43 | Machynlleth | |
| COR2 | Disused branch | 0.00 - 1.72 | Maespoeth Junction | |
| COS | Coltness Branch (Wishaw) | see separate portions | ||
| COS1 | Morningside Junction to Garriongill Junction | 14.15 - 15.29 | Polkemmet Junction | Originally Caledonian Railway, remiled continuation of North British Railway Morningside branch |
| COS2 | Morningside Junction to Coltness | 0.00 - 0.54 | Morningside Junction | See also MNG |
| COT | Cottam CEGB Branch | Now TYB1 | ||
| COU | Couston Branch | 0.00 - 0.74 | Couston Branch Junction | |
| COV | Colne Valley Branch | 50.28 - 69.28 | Liverpool Street via Marks Tey Junction (reverse) | |
| COW | Cowdenhill Branch | ?? - ?? | off Knightwood Branch; crosses Fulton St, Glasgow | |
| COY | Coley Branch | 0.00 - 1.61 | Coley Goods Junction | |
| COZ | Common Branch | 0.00 - 2.30 | Common Branch Junction | |
| CPB | Cameron Bridge to Pirnie Branch | 0.00 - 1.22 | Cameron Bridge | Served Leven Collieries Nos 1, 2, 3 & 4, Pirnie Colliery and Muiredge Colliery |
| CPC | Codnor Park Junction to Hammersmith (Midland Railway Centre) | 132.76 - 133.23 or 0.00 - 0.26 | St Pancras via Toton or Ironville Junction | Unclear which of two routes is intended |
| CPH | Craigentinny and Powderhall Branch | 0.00 - 2.12 | Powderhall Branch Junction | |
| CPI | Castleton and Bolton Line | see separate portions | ||
| CPI1 | Castleton South Junction to Castleton North Junction (Castleton South Fork Line) | 8.21 - 8.50 | Manchester Victoria | |
| CPI2 | Castleton North Junction to Bradley Fold Junction | 8.50 - 15.62 | Manchester Victoria | |
| CPI3 | Bradley Fold Junction to Bolton East Junction | 8.56 - 11.63 | Manchester Victoria via Besses o' th' Barn | |
| CPJ | Christ's Hospital to Peasmarsh Junction Line | 39.79 - 55.38/ 32.05 - 47.44 | London Bridge via Redhill/Waterloo via Guildford | Line remiled after closure; formerly GCH |
| CPL | Penarth Curve | 0.00 - 0.25 | Penarth Curve South Junction | |
| CPM | Castleford and Pontefract Monkhill Line | see separate portions | ||
| CPM1 | Pontefract West Junction to former Cutsyke Junction | 56.42 - 59.03 | Manchester Victoria via Rochdale, Wakefield Kirkgate and Pontefract Monkhill (reverse) | |
| CPM2 | Former Cutsyke Junction to Castleford West Junction | 0.00 - 0.61 | Castleford West Junction | |
| CPP | Crystal Palace Loop | 0.66 - 1.10 | Paddington | |
| CPR | Collins Paper Mills Branch (Sunderland South Dock or Pallion) | ?? - ?? | ||
| CPS | Cottam Power Station Loop | 71.79 - 74.15 | Manchester London Road via Woodhead | |
| CPY | Caerphilly Branch | 5.03 - 8.72 | Bassaleg Junction | |
| CPZ | Caerphilly Branch Down Loop Line | ?? - 5.37 - 7.13 | Bassaleg Junction | |
| CQR | Cheetham Hill Junction and Queens Road Junction Curve | 0.73 - 1.21 | Manchester Victoria | |
| CQS | Cardiff Queen Street North Junction | 1.16 - 1.25 | Cardiff Bute Road | Now treated as part CAR |
| CR_1 | Nuneaton Cemetary Sidings | 96.41 - 96.62 | London Euston | |
| CR_2 | Nuneaton South Sidings | 96.63 - 97.00 | London Euston | |
| CR_3 | Nuneaton Up Side | 97.01 - 97.29 | London Euston | |
| CR_4 | Nuneaton Down Side | 97.09 - 97.35 | London Euston | |
| CR_5 | Hartshill (Engineer's) Siding | 99.30 - 99.54 | London Euston | |
| CR_6 | unknown | 106.15 - 106.35 | London Euston | |
| CR_7 | Tamworth Low Level Up Side | 110.05 - 110.23 | London Euston | |
| CR_8 | Lichfield Trent Valley | 116.31 - 116.48 | London Euston | |
| CR_9 | Rugeley | 124.24 - 124.46 | London Euston | |
| CR10 | Stafford S&T Siding | 132.70 - 132.75 | London Euston | |
| CR11 | Stafford Up Arrival | 133.08 - 133.25 | London Euston | |
| CR12 | Stafford Salop Siding | 133.05 - 133.28 | London Euston | |
| CR13 | Stafford OTM Depot | 133.23 - 133.32 | London Euston | |
| CR14 | Stafford Universal Grinding Co | 133.61 - 134.08 | London Euston | |
| CR15 | Coventry Station | 93.62 - 93.72 | London Euston | |
| CR16 | Coventry South | 8.13 - 8.38 | Milverton Junction | |
| CR17 | Coventry North | 0.02 - 0.32 | Coventry North Junction | |
| CR18 | Coventry North | 94.08 - 94.19 | London Euston | |
| CR19 | Coventry | 94.07 - 94.14 | London Euston | |
| CR20 | Stechford | -0.15 - -0.01 | Stechford North Junction | |
| CR21 | Grand Junction Up and Down Through Siding | 0.40 - 0.52 | ||
| CR22 | Soho Electric Traction Depot | 2.05 - 2.31 | Birmingham New St | |
| CR23 | Watery Lane | 7.78 - 8.10 | Birmingham New St | |
| CR24 | Wolverhampton | 12.69 - 13.00 | Birmingham New St | |
| CR25 | Wolverhampton Engineer's Siding | 12.61 - 12.68 | Birmingham New St | |
| CR26 | Wolverhampton Down Side | 12.79 - 13.07 | Birmingham New St | |
| CR27 | Wolverhampton Up Side | 13.08 - 13.25 | Birmingham New St | |
| CR28 | Oxley Down Side | 143.14 - 143.41 | London Paddington | |
| CR29 | Oxley Up Side | 143.15 - 143.47 | London Paddington | |
| CR30 | Oxley Carriage Washing Siding | 143.36 - 143.62 | London Paddington | |
| CR31 | Basford Hall Down Sidings | 156.68 - 157.23 | London Euston | |
| CR32 | Basford Hall Up Sidings | 156.74 - 157.22 | London Euston | |
| CR33 | Basford Hall Coal Sidings | 157.22 - 157.39 | London Euston | |
| CR34 | Basford Hall South Yard | 157.26 - 157.47 | London Euston | |
| CR35 | Salop Goods Sidings | 157.26 - 157.51 | London Euston | |
| CR36 | Crewe Wagon Shop | 0.37 - 0.58 | Crewe South Junction | |
| CR37 | Crewe Brook Carriage Siding | 157.03 - 157.20 | London Euston | |
| CR38 | Crewe Brook Carriage Siding | 157.20 - 157.24 | London Euston | |
| CR39 | Crewe Down Holding Siding | 157.43 - 157.73 | London Euston | |
| CR40 | Gresty Road Sidings | 0.01 - 0.30 | Gresty Lane Junction | |
| CR41 | Gresty Up Sidings | 0.62 - 1.12 | Crewe South Junction | |
| CR42 | Gresty Down Sidings | 0.60 - 1.11 | Crewe South Junction | |
| CR43 | Hartford | 170.48 - 170.77 | London Euston | |
| CR44 | Chatterley Valley Disposal | 16.02 - 16.23 | Macclesfield Hibel Road | |
| CR45 | Longport Up Siding | 16.43 - 17.05 | Macclesfield Hibel Road | |
| CR46 | Longport Down Siding | 16.57 - 17.07 | Macclesfield Hibel Road | |
| CR47 | Basford Hall Down Sidings | 156.69 - 157.21 | London Euston | |
| CR48 | Cockshute Siding | 19.20 - 19.42 | Macclesfield Hibel Road | |
| CR49 | Stoke LNW Yard | 19.48 - 19.62 | Macclesfield Hibel Road | |
| CR50 | Stoke Freight Terminal | 19.17 - 19.60 | Macclesfield Hibel Road | |
| CR51 | Stoke Station Siding | 19.18 - 19.71 | Macclesfield Hibel Road | |
| CR52 | Marcroft Wagon Repair Siding | 21.01 - 21.43 | Macclesfield Hibel Road | |
| CR53 | Leek Brook Junction Siding | 0.01 - 0.27 | Leek Brook Junction | |
| CR54 | Oakamoor British Industrial Sand | 10.21 - 10.40 | Uttoxeter | |
| CR55 | Oxley Down Side | 143.18 - 143.39 | London Paddington | |
| CRA | Crayford: Spur A to Spur B Junctions | 16.11 - 16.41 | Charing Cross via Sidcup | |
| CRB | Cowbridge Road Junction to Bridgend | 18.35 - 18.76 | Barry Junction | Treated as part VOG |
| CRB | Moor Row to Cleator Moor | 2.24 - 3.38 | Mire House Junction | |
| CRC | Camden Road Junction to Camden Junction Line | see separate portions | ||
| CRC1 | Camden Road Junction to Camden Road Viaduct | 5.10 - 5.23 | Broad Street | |
| CRC2 | Camden Road Viaduct to Camden Junction | 5.23 - 5.78 | Broad Street | |
| CRD | Boundary with Talbot to St James Junction | 113.49 - 114.40 | ||
| CRE | Capeldrae (Westfield) to Redford Junction Branch (Thornton) | 27.78 - 33.04 | Stirling | |
| CRF | Camden Road to Finsbury Park Curve (including Kings Cross Goods) | see separate portions | ||
| CRF1 | Freight Terminal Junction to mileage change (Kings Cross Incline) | 0.00 - 0.30 | Copenhagen Junction (formerly known as Freight Terminal Junction) | Now part of NLI |
| CRF2 | Mileage change to Camden Road Central Junction | 4.45 - 4.64 | Broad Street | Now part of NLI |
| CRF3 | Kings Cross Yard | 0.06 - 0.34 | Freight Terminal Junction | |
| CRG | Commercial Road Goods Depot | 0.00 - 0.27 | Commercial Road Junction | |
| CRH | Cromer High Branch | 23.29 - 24.03 | Norwich | |
| CRI | Criggion Branch | 0.00 - ≈5.50 | Kinnerley | |
| CRL | Clarbeston Road and Letterston Line | 271.08 - 281.57 | Paddington via Stroud | |
| CRN | Charlestown Branch | 0.00 - 2.13 | Elbowend Junction | |
| CRO | Crossfields Branch | 2.24 - 3.38 | Mire House Junction | |
| CRP | Corstorphine Branch | 2.22 - 3.57 | Haymarket West Junction | |
| CRR | Chester and Rock Ferry Line | see separate portions | ||
| CRR1 | Chester West Junction to Hooton Junction | 0.19 - 7.70 | Chester | |
| CRR2 | Hooton Junction to Rock Ferry Station | 7.70 - 13.39 | Chester | |
| CRS | Cardiff Riverside Branch | Now CFR | ||
| CRS | Cromer and Sheringham Branch | 42.71 - 45.64 | South Lynn Junction | |
| CRT | Coursington Branch | 0.00 - 1.08 | Shields Colliery Junction | |
| CRY | Cardiff Railway | 0.00 - 9.28 | Heath Junction | 5.24 - 7.18 now in NAN |
| CRZ | Cawdor Branch | 14.73 - ≈16.13 | Llandilo Junction | |
| CSB | Crowhurst Sidley and Bexhill West Line | 57.59 - 62.15 | Charing Cross via Chelsfield | |
| CSC | Cable Street Coal Depot (London Commercial Road) | ?? - ?? | No apparent mileage, siding on up side of GER between Shadwell and Leman Street | |
| CSD | Castleton Depot | 7.72 - 8.64 | Manchester Victoria | |
| CSF | Croes Newydd South Fork (Wrexham South Curve) | 201.21 - 201.37 | Paddington via Didcot | |
| CSG | Crewe Salop Goods Loop | 156.26 - 157.55 | Euston | |
| CSJ | Clifton South Curve (Clifton to Nanny Goat Junction) | ?? - ?? | Links CGJ7 to EDE, approx 0.74 long | |
| CSM | Chislehurst to St Mary Cray Line | see separate portions | ||
| CSM1 | Chislehurst Junction to St Mary Cray Junction | 11.33 - 11.71 | Charing Cross | |
| CSM2 | Chislehurst Junction to Hawkwood Junction | 11.33 - 11.66 | Charing Cross | |
| CSM3 | Hawkwood Junction to St Mary Cray Junction | 11.69 - 12.30 | Charing Cross | |
| CSN | Cowlairs North Junction to East Junction Curve | 0.00 - 0.21 | Cowlairs East Junction | |
| CSP | Carstairs Curve | 73.49 - 74.10 | Carlisle via Carstairs (reverse) | |
| CSQ | Calstock Quay Branch | 0.00 - 1.25 | Branch junction | Sometimes SCQ used in error |
| CSS | Stonefield to Splott Junction (Cannon Street Goods) | 0.00 - 0.65 | Splott Junction | |
| CST | Carpenters Road North Junction to Stratford Central Junction West | 0.00 - 0.29 | Stratford Central Junction | |
| CSW | Coleford Branch (S&W) | Now CFS | ||
| CSW | Metropolitan Junction to Cannon Street South Junction | 1.35 - 1.49 | Charing Cross | |
| CSY | Chichester to Selsey Branch | 0.00 - 7.40 | Chichester | |
| CTA | Clifton Junction to Accrington Line | see separate portions | ||
| CTA1 | Clifton Junction to Radcliffe North Junction | 4.51 - 8.60 | Manchester Victoria | |
| CTA2 | Bury Loco Junction to Accrington North Junction | 8.63 - 22.02 | Manchester Victoria via Cheetham Hill Junction | |
| CTB | Colton Branch (Dunfermline) | 0.00 - 0.28 | Whitemyre Junction | |
| CTC | Cathcart Circle | 0.00 - 5.19 | Muirhouse North Junction | |
| CTD | Cadoxton and Trehafod Line | 0.00 - 16.53 | Cadoxton Junction | Formerly CTL |
| CTH | Colne Junction to Hythe Junction Curve | 0.00 - 0.22 | Colne Junction | |
| CTL | Cadoxton and Trehafod Line | Now CTD | ||
| CTL | Calder Bridge Junction to Turners Lane Junction Curve | 0.00 - 0.50 | Calder Bridge Junction | |
| CTL3 | unknown | 0.00 - 0.01 | unknown | Not in GEOGIS but present in a structure maintenance system |
| CTM | Cheltenham Branch | 2.70 - 7.03 | Gloucester | Formerly CHE. 2.70 - 5.71 now 90.23 - 86.71 ex Derby in BAG2 |
| CTP | Connington South Tip Sidings | 66.61 - 67.55 | Kings Cross | |
| CTR | Catrine Branch | 0.00 - 1.34 | Brackenhill Junction | |
| CTS | Coltness Branch | 0.00 - 0.67 | Morningside | North British Railway branch to Coltness Ironworks |
| CTY | City Link Line (Springburn to Pinkston Junction) | 0.00 - 0.30 | Cowlairs South Junction | Now PNS or ZZB5?? |
| CUL | Culm Valley Branch | 0.01 - 7.29 | Culm Valley Branch Junction | |
| CUS | Cudworth Station Branch | 52.71 - 53.63 | Hull Alexandra Dock | |
| CUZ | Cwmcapel Branch | 0.00 - 1.11 | Burry Port Docks | |
| CVA | Calva to Buckhill | 0.00 - 6.30 | Calva Junction | Formerly SBL2 |
| CVB | Cheddar Valley Branch | 14.02 - 31.57 | Witham East Somerset Junction | |
| CVL | Churnet Valley Line | 0.00 - 27.28 | Uttoxeter East Junction | |
| CVR | Cairn Valley Light Railway | 0.00 - 15.51 | Moniaive | |
| CVS | Chester South Junction to Chester North (or West) Junction | 0.00 - 0.24 | Chester West Junction | |
| CVZ | Carnarvon/Carnarfon Branch | 0.44 - 1.08 | Llandilo Junction | |
| CWB | Messers Cook and Co Works Branch | 2.55 - 2.64 | Treeton Junction | Cook's Tinsley Works at West Tinsley on Sheffield District line |
| CWD | Crewe Works Deviation | 157.79 - 158.01 | Euston | |
| CWE | Clayton West Branch | 7.67 - 11.22 | Huddersfield | |
| CWH | Cowdenbeath Branch | see separate portions | ||
| CWH1 | Inverkeithing to Cowdenbeath | 13.21 - 22.76 | Edinburgh Waverley | |
| CWH2 | Cowdenbeath to Lumphinnans | 0.00 - 0.70 | Cowdenbeath North Junction | |
| CWH3 | Lumphinnans to Thornton South Junction | 27.00 - 35.38 | Edinburgh Waverley | |
| CWJ | Camden to Watford Junction Line (DC Electric Lines) | 1.36 - 17.58 | Euston | |
| CWK | Hamilton Square and West Kirby Line | see separate portions | ||
| CWK1 | Hamilton Square to Mersey Tunnel | 1.60 - 3.00 | Liverpool Central Low Level | |
| CWK2 | Mersey Tunnel to Bidston | 3.00 - 4.40 | Liverpool Central Low Level | |
| CWK3 | Bidston to West Kirby | 4.40 - 10.46 | Liverpool Central Low Level | |
| CWL | Central Wales Line | see separate portions | ||
| CWL1 | Junction with SHL to original zero point | 20.01 - 20.12 | Shrewsbury | |
| CWL2 | Original zero point to Llandovery | 0.00 - 59.14 | Central Wales Junction | |
| CWM | Coopers Lodge Junction to Wimblebury Mine | ?? - ?? | ||
| CWN | Cockermouth and Workington Line | 0.00 - 8.12 | Cockermouth Goods station | |
| CWO | Cleator and Workington Line | 0.00 - 10.06 | Cleator Moor Junction | |
| CWP | Camden Washing Plant | ≈1.03 - 1.36 | Euston | |
| CWR | Cattewater Branch | 0.43 - 1.64 | Turnchapel Branch Junction | |
| CWS | Clipstone West Junction to South Junction Curve | 10.66 - 11.04 | Kirkby South Junction via Mansfield | |
| CWT | Caerwent Branch | 0.00 - 3.29 | Caerwent Branch Junction | |
| CWZ | Cwmbach Branch | 22.00 - 22.52 | Cardiff Bute Road | Part now ALK |
| CXL | Caldercruix Lower Branch | 0.00 - 0.41 | Caldercruix West signal box | Caldercruix Paper Mills branch |
| CYA | Cylla Branch | 13.72 - 15.08 | Cardiff East Dock | |
| CYC | Chinley Chord | 167.55 - 168.32 | St Pancras | |
| CYD | Chatham Dockyard Branch | 0.00 - 2.43 | Gillingham Junction | Formerly CDO |
| CYL | Crimea Yard Branch | 0.71 - 1.38 | Paddington | |
| CYM | Cymmer Junction Loop | 11.11 - 11.32 | Bridgend | Formerly CMR |
| CYW | Canterbury and Whitstable Line | 70.34 - 76.41 | Charing Cross via Chelsfield | |
| CYY | Scarborough Goods Lines | 0.00 - 0.38 | York Yard South Junction | Also known as Clifton York Yard, or as York Turning Triangle |
| CYZ | Clydach Loop | 0.00 - 0.46 | Felin Fran West Junction | Not completed |