"Then, hard times came. The mines in the hills closed."
— The Narrator, Granpuff

Bertram's Old Mine was one of the mines on the Mid Sodor Railway, which was owned by Sodor Gold Company at the time until the company and mine closed down. Bertram and Mine Engine used to work here.

At some point, Bertram was abandoned here and nature overgrew the mine and all the leftover scrap. Many years later, Toby discovered the mine when he took Sir Topham Hatt and his grandchildren exploring. Whilst on guard one night, Toby found Bertram, now they, Skarloey and Rheneas take visitors to and from the attractions that have been built on the site. There is also a small station build at the mine.