The interiors of the Caves of Hercules have been used as dwellings for centuries, and there are several quarries and passages between them. Only a small percentage of the caves are open to visitors. The Caves of Hercules are reputed to have been the home of Hercules who founded Tangier and made the Straits of Gibraltar with one blow from his sword.
Most of the cave was carved out by the ancient Moroccans, who used the resulting stones to grind grains.