The Old Stone Bridge is a small bridge made out of stone located near a large forest.
The bridge first appeared in the fifth series episode, Haunted Henry. In Busy Going Backwards, some workmen were working on the bridge when they were warned of Toad and his runaway trucks. They diverted the runaway train onto an old siding beside the bridge, causing it to crash into muddy water that had pooled in the middle of the siding. In an eighth series learning segment, the bridge was revealed to have rails running above it.
- In Busy Going Backwards, the workmen were shown building a second track running underneath the bridge, but in Percy and the Haunted Mine, the bridge still ran over only one track. An eighth series Learning Segment finally showed the second track.
- While the workmen were building a second track underneath the bridge in Busy Going Backwards, it had a lorry on top of it, but in Learning Segments, there are rails on top of it, indicating that the rails were built there.
- The model of the bridge was recycled as a river bridge in Sir Topham Hatt's Holiday and Duncan and the Old Mine.
- It is unknown where the bridge is located but it is likely that it is somewhere on the west part of the Island.