 Some of these channels were artificial, as the 1st century geographer Strabo recorded.Modern excavation has found enormous channels dug in the 14th century BCE which drained water into the sea to the northeast; Strabo mentions work being done on these channels by an engineer named Crates of Chalcis in the time of Alexander the Great.Homer and other ancient authors refer to Copais as the "Cephisian lake", named for the river Cephissus.