The Downpatrick and County Down Railway (DCDR) is a five-foot, three-inch (1,600 mm) gauge heritage railway in County Down, Northern Ireland. It is operated by volunteers and runs passenger trains using steam and diesel locomotives, diesel railcars, and vintage carriages. The railway has approximately four miles (6.4 km) of track in a triangular-shaped layout, which connects the town of Downpatrick with the historical sites of Inch Abbey to the north and King Magnus’ Grave to the south. It also houses a museum of railway artefacts and rolling stock originating from both Northern Ireland and the Republic of Ireland, dating from the 1860s to the 1980s.