The Dundee and Arbroath Railway was an early railway in Scotland. It opened in 1838, and used the unusual track gauge of 5 ft 6 in (1,676 mm). In 1848 it changed to standard gauge and connected to the emerging Scottish railway network. It was absorbed by the larger Caledonian Railway, but when the North British Railway completed the construction of the Tay Bridge in 1878, it was granted part ownership of the line to enable it to form its main line to Aberdeen, so the line became the Dundee and Arbroath Joint Line.