South Wales Railway
The South Wales Railway was a broad gauge railway that linked the Gloucester and Dean Forest Railway with Neyland in Wales.
The railway was created to meet the need to ship coal from the South Wales valleys to London, and secondly to complete Brunel's vision of linking London with New York, and more financially rewarding, to the South Wales coal and ferries to Ireland.
A prospectus was issued in 1844 to build a railway through South Wales from a junction with the Great Western Railway at Standish in Gloucestershire. The proposed route would cross the River Severn west of Gloucester, and run through South Wales to Fishguard, thereby connecting to both southern Ireland and New York. The Great Western Railway agreed to subscribe £600,000 of the £2,400,000 required to build the railway.
However, local objections were raised over the proposed long bridge over the River Severn. The objections were overcome by linking with the Gloucester and Dean Forest Railway at Grange Court, and linking with the rest of the existing broad gauge system at Gloucester. This diversion added an extra 18 miles to the journey between South Wales and London.
The initial part of the line between Chepstow and Swansea was opened on 18 June 1850, with trains operated by the Great Western Railway under a lease agreement. At the eastern end of the line the connection to Gloucester and London was completed in July 1852 when the bridge at Chepstow was finished. Construction of the line west of Swansea was delayed, due to the financial problems of the late 1840s, and the abandoning of construction of the Irish railways that would connect with the Fishguard ferries at Waterford. The western terminus of the line was changed from Fishguard to New Milford (Neyland) and the line west of Swansea was built in stages, reaching New Milford in April 1856.
As coal traffic from the South Wales Valleys increased, the tensions between the South Wales Railway and the Great Western Railway increased due a lack of wagons. These were eventually resolved when, in January 1862, the two companies merged.
In 1886, the direct route to South Wales was implemented with the opening of the Severn Tunnel between Bristol and Severn Tunnel Junction.
Sources of Information
-  Wikipedia