Mina Proano is one of the largest producers of silver in world. The mine has been in almost continous use since the C16th. There are two extant engine houses on the site which still contain cornish beam engines (not accessible to the public). There is a good museum in the old school of mines and a tourist mine which exits above the old opencast workings. The tourist mine is a bit disappointing as all the walls underground are cover in shotcrete.