Botallack mine. Situated at Botallack, a village situated between Pendeen & St.Just, Cornwall. This was a former tin mine (copper & arsenic were also mined here, but in lesser quantity than tin). The mine, that extended out beneath the sea, closed in 1895. The photo shows the remains of the engine house.
iWalk Porthtowan to Chapel Porth - a circular walk from Porthtowan, along the coast, valleys and woodland passing engine houses and other relics of Cornish copper mining - 4.7 miles - moderate - http://iwkc.co.uk/wa/133. Photos on the route: https://www.pinterest.com/iwalkcornwall/iwalk-porthtowan-to-chapel-porth/