1. Brynkinalt Colliery was developed during the 1860s by Brynkinalt Coal Co. Ltd. At its peak in 1923 the colliery had a workforce of 1675. It remains disused since its closure by the National Coal Board in November 1968.

Source: http://www.welshcoalmines.co.uk/North/westminster.htm Viewed 19 November 2007
RCAHMW, 19 November 2007

2. Former colliery first opened in c1870 and extended eastwards c1912 and eventually connected to the Ifton Colliery at St Martins. The coal working ceased 1928 after which Brynkinallt was maintained as a ventilation shaft. The colliery was closed in 1968 and landscaped in the 1970s. The only structural remains at ground level are a brick and concrete structure surrounding No.1 shaft and slight earthworks indication the location of the adjacent winding house.

RCAHMW, 18th August 2008