Bertram, nicknamed "The Old Warrior" for his bravery, is an old narrow gauge engine who worked in a quarry on the far side of the island.
Bertram used to work in the mines with the other little engines in a remote part of Sodor. His fate was unknown to many after the mine's closure, and it was assumed he was left to rust. He remained at the mine until it was rediscovered years later.
Over time, he became legendary; many knowing of the "old warrior ghost" haunting the mine. However, Toby found him whilst watching over the quarry one night, and has since befriended him. He now works at the restored mines, taking passengers to the fairground within.
Bertram is an old engine who works at the restored mine taking passengers to the fairground that is at the mine. He is considered incredibly brave. When Toby first saw him, he thought Bertram was a ghost. Since they have met, Bertram and Toby have become good friends. If there are any ghosts there, they certainly make the place seem very happy.
Bertram is based on Prince, a George England tender engine on the Ffestiniog Railway. Duke is another member of this class.
Bertram is painted dark brown with red lining, in some of his merchandise, he has two brown plaques on either side of his saddletank with his name written in gold.