In pre-Roman times the region was populated by the Astures, a Hispano-Celtic Gallaecian people. They were conquered by Emperor Augustus in the Astur-Cantabrian Wars (29–19 BC) and the area quickly became the largest mining center of the Empire during the Roman period, where gold and other metals and minerals were extracted. Numerous Roman mining sites are still visible in the area, one of the most spectacular being Las Médulas, a UNESCO World Heritage Site since 1997. Romans also imported grapevines, and wine production thrived in the region until the propagation of Phylloxera at the end of the 19th century, which destroyed the majority of the vineyards.