DisgrifiadThe Great Mountain Colliery went into production in the late 1880s and became the most productive colliery in the Gwendraeth valley. The colliery closed in 1962. The No 1 drift stayed open for a number of years after this date as a pumping station.
References: OS historical mapping; www.welshcoalmines.co.uk
RCAHMW, 2015.