Las Médulas

Las Médulas is a historic gold-mining site near the town of Ponferrada in the comarca of El Bierzo [1]. It was the most important gold mine, as well as the largest open-pit gold mine, in the entire Roman Empire [1]. The spectacular landscape of Las Médulas resulted from ruina montium, a Roman mining technique described by Pliny the Elder in 77 AD [1]. The technique employed was a type of hydraulic mining which involved undermining a mountain with large quantities of water [1]. Large-scale production did not begin until the second half of the 1st century AD [1].