The 26.4 km 914 mm gauge railway from Douglas, capital of the Isle of Man, through Castletown to Port Erin in the south of the island opened in 1874. It is the only section that remains of a much larger system. The line is still operated with some of its original locomotives and carriages. It has passed through many changes in ownership but is now managed by the Manx government.
The railway’s museum at Port Erin, displays two locomotives, the Queen’s coach and the governor’s saloon, together with numerous smaller items. All but one of the railway’s sixteen locomotives were supplied by Beyer Peacock of Manchester between 1873 and 1926. Four are normally in traffic, two are in the museum, and one is sectioned in the Museum of Science and Industry, Manchester. The line is usually open during the tourist season between March and early November.