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 works 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.
Whilst on guard one night, Toby found Bertram. Following this, the mines were re-opened as an attraction for visitors on Toby's Branch Line, with a narrow gauge line operated by Bertram. Skarloey and Rheneas occasionally work here and were present for its re-opening. There is also a small station at the mine.
Harry Topper ran the fair. He soon left the mine and reopened business at the nearby Tidmouth Bay. The mine was reopened as a mine and has had casual slate and gravel traffic ever since.