The Carmarthen and Cardigan Railway was a 7 ft 1⁄4 in broad gauge railway line in Wales that was intended to connect Carmarthen on the South Wales Railway with Cardigan. In fact, it was unable to raise the necessary capital and was loss-making from the time of opening the first short section of its line in 1860, and it was in receivership for much of its life. It eventually reached Llandysul in 1864 but was not extended further during its independent existence.

The Burry Port and Gwendraeth Valley Railway (BP&GVR) was a mineral railway company that constructed a railway line in Carmarthenshire, Wales, by conversion of a canal, to connect collieries and limestone pits to the sea at Kidwelly. It extended its network to include Burry Port, Trimsaran and a brickworks at Pwll, later extending to Sandy near Llanelli. For a time the company worked the separate Gwendraeth Valleys Railway. The BP&GVR was notable because of the very low height of some overbridges, a legacy of the canal conversion.