Gauge: 3ft 6in (2.06 metres)
Constructed under the Merthyr Tydfil Light Railways Order of 1899, and owned and operated by the Merthyr Tydfil Electric Traction & Lighting Company Ltd (a BET subsidiary), this electric tramway opened on 6 April 1901.
The 3ft 6ins gauge system originally ran from Cefn Bridge on Brecon Road to the Bush Inn outside Dowlais Ironworks on Dowlais High Street, via Williamstown, Pontmorlais Circus, Penydarren Road, High Street and Penydarren New Road, a distance of about 2½ miles. At Pontmorlais Circus a branch line travelled from the Owain Glyndwr along Pontmorlais High Street to Graham Road, passing the Great Western Railway’s Merthyr Station.
The initial rolling stock consisted of thirteen (Nos. 1-13) Midland single-deckers and three (Nos. 14-16) ERTCW open-top double-deckers. The depot and power station were built in Trevithick Road on the site of the Penydarren Ironworks.
A half mile extension from Cefn Bridge to Cefn High Street was opened in 1914.
The tramway remained in operation until 1939, when Merthyr Tydfil Corporation, faced with the problem of trams obstructing the growing traffic in the narrow streets, purchased the system from the BET for £13,500 so that the tramway could be closed down. The last tram ran on 23 August 1939, and Merthyr Tydfil was able to operate its own buses along the tram routes, which it had previously been prevented from doing by the provisions of the Merthyr Tydfil Corporation Act of 1920 that had prohibited buses competing with the trams whilst they still provided a service.
Information from The Directory of British Tramways (Keith Turner, PSL 1996)