'On the east side of Cwm Cregan, a small side valley branching off the Afan Valley, modern OS maps mark a series of `grottos?. In actuality they are underground stone quarries, probably dating from the late nineteenth century (the site is shown on the first and second editions of the 25inch OS maps, published in 1877 and 1899). Four `grottos? are shown on the current 1:25,000 scale map, but only one is still open today (although sealed by a metal fence). This has a large opening leading to a spacious chamber extending for about 30m into the hillside, with two side passages, the roof being supported by unquarried pillars of rock. The entrances to the other caves have presumably been filled in with earth and rubble.'
Notes written by Paul Davis to accompany photographs taken in January 2020
RCAHMW, 18th February 2020
