 In the early years of the twentieth century consideration was given to relieving the issue, and the decision was taken to construct what became the Swansea District Line.This long new line left the main line near Briton Ferry and looped round to the north of Swansea, joining the Llanelly line near Bynea.To give good access for colliery traffic, there was a triangular junction there, so that coal traffic from the Amman valley could turn east on to the new line; at the same time express passenger trains (particularly Fishguard boat trains) could avoid Swansea using the line.