|This article is about the Mountain Line. You may be looking for the Mountain Road.|
The Mountain Line is a line that winds alongside a mountain on the Skarloey Railway. Here Duke gave a great effort in pushing Stuart after he came to rescue him in You Can't Win. The line was also used to represent part of the Mid Sodor Railway in the fourth season.
- The location of the line changed in the sixth season, with the lake disappearing and trees replacing it.