 The first section of line between Carmarthen and was opened in 1860 by the Carmarthen and Cardigan Railway.This was extended by the original company to and eventually to Newcastle Emlyn, by the GWR in the 1890s, but never reached Cardigan.The section from Carmarthen to Llandyssul was built as a broad-gauge route, with a third standard-gauge line added as far as Pencader Junction later, after the M&MR line was built.