Constructed during the 1920s and opened on 16 July 1927, the Romney, Hythe & Dymchurch Railway was the dream of millionaire racing drivers Captain J.E.P. Howey and Count Louis Zborowski. Zborowski had constructed a railway at Higham Park, his home at Bridge, Kent, and agreed to donate the rolling stock and infrastructure to the project. Zborowski however was killed in a motor racing accident at Monza before the Romney Marsh site was chosen, and Howey continued the project alone.

The locomotives were designed by engineer Henry Greenly who worked with Captain J E P Howey.[1] Greenly also served as the railway's first Chief Engineer.

Mountain Class 'Hercules' hauled the inaugural train from Hythe to New Romney with guests including the mayors of the two towns, and General Sir Ivor Maxse. Howey was not happy with just 8 miles (13 km) from New Romney to Hythe and he extended 5 1⁄2 miles (9 km) from New Romney to Dungeness. This section was originally double track, but is now single due to damage during World War II, when the line was taken over by the military. A miniature armoured train was used on the line.[2] After the war the line re-opened between Hythe and New Romney in 1946, with the singled New Romney to Dungeness section reopened in 1947 by Laurel and Hardy.

As well as being a tourist attraction, this railway is a public service between the small towns and villages between Hythe and Dungeness and is under contract to the local council to transport children to and from The Marsh Academy in New Romney. The railway is expanding its role as part of the public transport network; Warren Halt re-opened in 2009 to provide a transport link to the Romney Marsh Visitor Centre, and discussions are taking place with local councils for the expansion of Burmarsh Road and the provision of a new station at the gravel pits in West Hythe, both in connection with proposed extensive new housing construction, and the need to provide alternative transport to the A259 coast road.[3]

All ten original locomotives remain in service, covering thousands of miles each year. The fleet, already one of the largest of any 15-inch (380 mm) railway in Britain, was expanded in 1976 with German-built locomotive no.11 'Black Prince' (formerly 'Fleißiges Lieschen' = 'Busy Lizzie'). The RH&DR is still the only user of the 4-8-2 "Mountain" locomotive in the UK, with No. 6 'Samson' and No. 5 'Hercules' in regular service. Two diesels, No. 12 'John Southland'(- later renamed J B Snell in May 2014) and No. 14 (Nameless - later 'Captain Howey'), were constructed in the 1980s.

The line carries 100,000 passengers each year.

The railway celebrated its 80th birthday in 2007 with a week of celebrations including reconstructions of scenes on the railway over the previous eight decades