Sodor would be between England and the Isle of Man, isolated from the British railway system, but somewhere that readers could easily imagine.

Awdry and his younger brother George worked out Sodor's history, geography, industry and language ("Sudric").

[citation needed] The names of some of the "historical" characters – used in the background but not appearing in the stories – were taken from locations on the Isle of Man, such as Sir Crosby Marown (Crosby is a village in the parish of Marown) and Harold Regaby (Regaby is a tiny hamlet on the parish boundary between Andreas and Bride).

[5]Below are some words and phrases, and place-names translated into English: Sodor is usually shown as much larger than the Isle of Man.

Its north-west coast is separated from the Isle of Man by a strait called the Sudrian Sea (Faarkey-y-Sudragh), four miles (6 km) wide.

The capital and administrative centre of Sodor is the city of Suddery; Tidmouth is the largest town on the island.

They are linked to and interoperable with each other and with the mainland system, so that the standard-gauge engines can visit locations in Britain under their own power.

Rolling stock is moved to and from the narrow-gauge railways on flatbed wagons on the standard-gauge system; for example, Rheneas is sent away for repairs in Skarloey Remembers and returns in Gallant Old Engine.