The ‘Lady’s Falls’ are formed where the Afon Pyrddin drops 20 ft (6 m) over a lip of the ‘Twelve Foot Sandstone’. The lady concerned was one of the many daughters of Brychan, the 5th-century King of Brycheinog. The sandstone tilts gently to the south so forcing the waters of the Pyrddin up against the foot of a high cliff of mudstone and over the left-hand side of the rock lip (when viewed from below). In higher water conditions the fall gradually extends further to the right. The upper surface of the sandstone is roughly patterned with the fossil roots of trees. A rocking stone (now dislodged) sits on this bench some 50 metres (160 ft) north of the falls.