The Ffarquhar Branch Line is Thomas' own line. He loves it dearly and considers it the most important part of the entire railway. He earned it after helping James from a nasty accident due to some cars.
Thomas, Stanley and Daisy run passenger duties with Annie and Clarabel. Toby, with Henrietta, Victoria, and Elsie, and Flora with her unnamed bilevel coach, run trains to Anopha Quarry. Percy and Rosie are in charge of goods duties, although when Thomas is absent they take over passenger duties. He and Toby also appear to share the workload of stone trains to Knapford Harbour. Stepney, Duck, and Wilbert have also worked on the branch at various points.
The branch also has a goods-line from Toryreck to Knapford Harbour, worked by Percy. This line also has a connection to the Dryaw mines, formerly used for mining lead but now being worked for deposits of uranium.
The quarry tramway extends five miles from Ffarquhar, through the streets of the village, then into the hills to the private sidings of Anopha Quarry. This tramway is property of the Ffarquhar Quarry Company and was formerly worked by Toby, but more recent arrangements have allowed for Mavis to operate trains on it.
The branch carries passengers, quarry stone, farm produce, dairy products from St. Pedroc's Dairy in Elsbridge, general goods, and uranium from the mines. Some passenger trains work into Tidmouth to pick up a through coach from the Wild Nor' Wester.