Brecon and Merthyr Railway
The Brecon and Merthyr Tydfil Junction Railway (B&M) was a railway in Wales running from Brecon, Brecknockshire to east of Merthyr Tydfil, Glamorgan. It was one of several railways that served the industrial areas of Glamorgan and Monmouthshire along with the Taff Vale Railway (TVR) and Great Western Railway (GWR).
The line opened in stages in the 1860s, including the Beacon Tunnel at Torpantau (Official Railway name Torpantau tunnel), 1313 feet above mean sea level, the highest railway tunnel in Britain, and a 7-mile north to south approach to the tunnel on a 1:38 2.6 % rising gradient. The line's highest point at 1314 feet, was in the railway cutting above Fochriw. Though it survived through to nationalisation in 1948, it was never profitable and consequently passenger services were withdrawn in 1962 with a complete closure to freight services to Brecon in 1964. A section of the line is now occupied by the 1 ft 11 3⁄4 in (603 mm) gauge Brecon Mountain Railway .
In 1836, Sir John Josiah Guest, of the Dowlais iron Works, had written of his proposal to construct a railway linking Dowlais to the valley of the River Usk, and possibly also running into Brecon. The line would have pretty nearly covered the same route as was eventually adopted by the B&M. A similar proposal suggested a line running up the Taf Fawr valley over the Brecon Beacons via Storey Arms and thence to Brecon.
The company was established by a Bill of 1859, financially supported by several prominent Brecon citizens, and the complete route from Brecon to Merthyr Tydfil was authorised the following year. The first section to open was a 6.75 miles (10.86 km) section between Brecon and Talybont-on-Usk in 1863, which reused a section of a horse-drawn tram line. The Beacons tunnel (also known as Torpantau tunnel) opened in 1868. The complicated series of amalgamations (including its originator the Hay Railway, a tram-road worked by horses opened in 1816) can best be appreciated here to explain how the B&M came about. In fact the B&M used the Hay Railway as the basis for its route between Talyllyn and Brecon. This included the tramroad tunnel (see below) at Talyllyn which required widening and deepening to allow the passage of standard gauge trains.
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