Small pit accessed by a tunnel in a cutting. Stated to have ‘investigative tunnels leading north east on both floors.’

Higher bench can be accessed directly. Traversing the pit on the left, there’s a low slate wall and vegetation hiding a ‘secret passage’. Not yet entered.

1930s development on the site of 19C trials which consisted of shallow cuttings. The meagre output was raised by cable to Moel Tryfan, the hefty anchorage of which remains by the 1937 mill.