The North Western Railway is a privatised railway company operating train services on the Isle of Sodor in the Irish Sea, between Cumbria and the Isle of Man. The company was formed in 1915 upon the amalgamation of the Sodor & Mainland; Tidmouth, Knapford & Elsbridge and Wellsworth & Suddery Railways, linking the island to the Furness Railway of Barrow in Furness on the mainland.

The railway is notable for its usage of steam traction on major services, and this survived the downfall of steam engines on British Railways in 1968. The railway became privatised in 1997 after running under British Railways control for nearly 50 years.

The Sudrian Main Line runs from the fishing port of Tidmouth to Barrow in Furness, via the major Sodor towns of Knapford, Wellsworth, Cronk and Crovan's Gate. It connects with Network Rail lines at Barrow and there are some through trains from the Cumbrian Coast which operate on the island, notably on its eastern branch lines.

There are six branch lines on the island, serving the following settlements - Arlesburgh; Elsbridge & Ffarquhar; Suddery & Brendam; Peel Godred; Kirk Ronan and Ballahoo & Norramby. Some of these have diesel-hauled services operating on them, however steam is still the primary power over most of the Sudric metals.