As Railway Operation Simulator was originally built as a simulation of railways within the UK, the available signal types are based on the UK signalling system.
| Photo | Track Element | Signal Type | Description |
|---|---|---|---|
| Two-Aspect | The simplest type which can display aspects of Clear and Danger | ||
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Three-Aspect | Displays aspects of Clear, Danger and Caution, with the last aspect indicating either that the next signal is at Danger, or the route is terminating. | |
| Four-Aspect | Displays all aspects described above with the addition of Preliminary Caution which indicates the next signal is at Caution. |