Archaeology suggests that gold extraction on this site may have started sometime in the Bronze Age, possibly by washing of the gold-bearing gravels of the river Cothi, the most elementary type of gold prospecting. Sextus Julius Frontinus was sent into Roman Britain in AD 74 to succeed Quintus Petillius Cerialis as governor of that island. He subdued the Silures, Demetae and other hostile tribes of Roman Wales, establishing a new base at Caerleon for Legio II Augusta and a network of smaller Roman forts fifteen to twenty kilometres apart for his Roman auxiliary units. During his tenure, he probably established the fort at Pumsaint in west Wales, largely to exploit the gold deposits at Dolaucothi. Frontinus later restored the Aqueducts of Rome and wrote the definitive treatise on 1st century Roman aqueducts, the two-volume "De aquaeductu".