When you visit Minera Quarry and the surrounding area an amazing secret lies beneath your feet.

Since the first discoveries of the cave system at Minera in the 1960s, over 8 kilometres of caves have been mapped, most entered by man for the first time. Underneath the high moorland of Esclusham Mountain, underground streams have, over hundreds of millennia, widened fissures in the limestone to create cave passages. Tributaries converge on a ‘trunk passage’ of large dimensions, through which the main drainage from the mountain formerly collected in its journey northwards to springs in the River Clywedog. Dry ‘fossil’ caverns are extensive and often reach an impressive size. This cave system, though not well known, is a unique and spectacular feature in the North Wales region, and well deserves to be seen by a wider public. The cave system has statutory protection from Natural Resources Wales through its status as a ‘Site of Special Scientific Interest’ (SSSI).