A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
| ELR | Route | Section | Remarks |
|---|---|---|---|
| RAC | Radford Jn to Kirkby Lane End Jn | ||
| RAD | Radyr Branch | Radyr Branch Jn to Radyr Jn | |
| RBS1 | Rugby, Birmingham, and Stafford Line | Rugby Trent Valley Jn to Birmingham New Street | |
| RBS2 | Rugby, Birmingham, and Stafford Line | Birmingham New Street to Bushbury Jn | |
| RBS3 | Rugby, Birmingham, and Stafford Line | Bushbury Jn to Stafford | |
| RBY | Wherry Lines | Reedham to Berney Arms to Great Yarmouth | |
| RCB | Rutherglen to Coatbridge (R&C) Line | Rutherglen East Jn to Coatbridge Jn | |
| RDB | Runcorn Duke’s Dock Branch | Runcorn Jn to Folly Lane (NR boundary) | Understood to be part closed |
| RDG1 | London Waterloo to Reading | Waterloo (Windsor Lines) to Wokingham Jn | |
| RDG2 | London Waterloo to Reading | Wokingham Jn to Reading | |
| RDK1 | Ramsden Dock Branch | Salthouse Jn to Ramsden Dock | Known anomalies with data source accuracy |
| RDO1 | Channel Tunnel Rail Link (CTRL / HS1) | London St Pancras International to York Way South Jn | CTRL Relief line |
| REB2 | Redmire Branch | Castle Hills Inner Jn to Redmire (Tarmac) | |
| REB4 | Redmire Branch | Castle Hills Jn to Castle Hills Inner Jn | |
| RED1 | Redhill Branch | Stoats Nest Jn to Coulsdon ELR change | |
| RED2 | Redhill Branch | Coulsdon ELR change to Earlswood Jn | |
| RET | Retew Branch | St Dennis Jn to Gaverigan | Understood to be disused |
| REX1 | Ollerton West Jn to ELR change (Rexco Sidings) | Understood to be disused | |
| REY1 | Ramsgate Sidings | Sidings 1 to 5 | |
| REY2 | Ramsgate Sidings | Sidings 6 to 25 | |
| RFR | Reading Feeder Relief Lines | ||
| RGY1 | Rugby Up Sidings to South TMD and Carriage Sidings | ||
| RGY2 | Rugby Up Sidings | North & Stabling Sidings (excludes Front Sidings) | |
| RHD1 | Rosyth Dock Branch | Inverkeithing South Jn to 1 MP | |
| RHD2 | Rosyth Dock Branch | 1 MP to Rosyth Dockyard NR boundary | |
| RIC1 | Kay Park Jn to Riccarton (Riccarton Loop) | Kay Park Jn to former Bellfield Jn | |
| RIC2 | Kay Park Jn to Riccarton (Riccarton Loop) | Riccarton to former Bellfield Jn | |
| RLL | Reading Low Level Goods Lines | ||
| RLY | Ripple Lane Yard | ||
| RMY | Roath Marshalling Yard | ||
| RNC | Rutherglen West Curve (or North Chord) | Rutherglen West Jn to Rutherglen North Jn | |
| RNJ | Reading Spur Jn to Reading New Jn | ||
| RNS | Ramsgate New Sidings | ||
| ROA | Roath Branch | Tidal Sidings to Splott Jn | |
| ROC | Roath Dock Branch | Pengam Jn to Tidal Sidings | |
| ROS | Glascoed Branch | former Little Mill Jn - Glascoed | Understood to be disused |
| ROT | Redcar Ore Terminal Branch | Redcar Ore Terminal Jn to Redcar Ore Terminal | |
| ROU | Romford Branch | Romford Jn to Upminster | |
| RPE | Leatherhead Line | Raynes Park Jn to Epsom Jn | |
| RRN1 | Rugeley to Ryecroft Line | Ryecroft Jn to Cannock | |
| RRN2 | Rugeley to Ryecroft Line | Cannock to Rugeley North Jn | |
| RRN3 | Rugeley to Ryecroft Line | Rugeley Power Station | |
| RSB | Rhondda and Swansea Bay Line | Dynevor Jn to Jersey Marine South Jn | |
| RSC | Roundwood Chord | Roundwood Chord Jn to Silverwood Colliery | |
| RSJ | Redhill to Shalford Jn (via Guildford Line Jn) | ||
| RSL1 | Langloan Jn to Whifflett North Jn | Langloan Jn to former Rosehall Jn | |
| RSL2 | Langloan Jn to Whifflett North Jn | former Rosehall Jn to Whifflet North Jn | |
| RSW | Rose Street Curve (or Inverness Avoiding Line) | Welsh’s Bridge Jn to Rose Street Jn | |
| RTC | Reading Traincare Depot | ||
| RTJ1 | Romsey Jn to Tunnel Jn | Romsey Jn to Redbridge Jn | |
| RTJ2 | Romsey Jn to Tunnel Jn | Romsey Jn to Tunnel Jn | |
| RTR1 | Reading Triangle | DMU Sidings | |
| RTR2 | Reading Triangle | Loco Depot | |
| RTS | Rugby and Leamington Line | Rugby Trent Valley Jn to New Bilton | Understood to be part closed |
| RTT | Redhill Tonbridge Line Jn to Tonbridge West Jn | ||
| RUB1 | Rufford to Bilsthorpe Colliery | Rufford Jn to Bilsthorpe Colliery Jn | Understood to be disused |
| RUB2 | Rufford to Bilsthorpe Colliery | Bilsthorpe Colliery Jn to Bilsthorpe Colliery | Understood to be disused |
| RUC1 | Rufford Colliery Jn to Rufford Colliery Headshunt | Understood to be disused | |
| RUC2 | Rufford Colliery to Headshunt Jn for Rufford Colliery | Understood to be disused | |
| RUD | Ruddington Chord | Loughborough South Jn to NR boundary | |
| RVC | Ravensbourne Chord | Ravensbourne Chord Jn to Shortlands Jn | |
| RVS1 | Riverside Line | former Clydebank Central Jn to COM | Understood to be disused |
| RVS2 | Riverside Line | COM to Dalmuir Riverside | Understood to be disused |
| RWC | Reading West Curve | Reading West Jn to Oxford Road Jn | |
| RWS | River Wear Commissioners | Londonderry Sidings to Sunderland Docks | |
| RYH1 | Hyde Branch | Romiley Jn to Woodley Jn | |
| RYH2 | Hyde Branch | Hyde Jn to Woodley Jn to Hyde Jn |