Throughout the twentieth century the line continued as a main artery for coal distribution from the Gwendraeth valley, until the closure of Cynheidre Colliery in 1989.
The Llanelli and District Railway Society (L&DRS) ran an unsuccessful campaign lasting almost ten years to save the intact but derelict line.
The railway was sold in the mid 1990s by the British Rail property board to the local authorities as part of a scheme to transform the track bed into a cycle way.
The primary objective is to achieve a running line of one mile (1.6 km) consisting of a platform, loco shed, heritage centre, gift shop and café.
The LMMR operates and in some cases owns the following rolling stock: In addition to a British Rail Class 122 Bubble Car unit, the L&MMR is currently host to four Pacer DMUs: