| Junctions and other features | Running Lines | Stations, Signal Boxes and Junctions | Distance from Signal Box above | Loops and Refuge Sidings | Notes | |
|---|---|---|---|---|---|---|
| Maximum permissible speed 40 m.p.h. | ||||||
| 1 |
 |
↕ | Caernarvon No.2 | - | ||
| 2 | ↕ | Pontrhythallt | 5m 1299yds | |||
| Cwm-y-Glo Station | ||||||
| 3 | --- | ↕ | Llanberis Station | 3m 364yds | ||