Lake Caanthus (pronounced CAHN-thus, with a soft th) is a body of water in the Viridian province of Attalea Major. Located at a relatively high elevation, through aqueducts the famously pure water of the lake is supplied to cities as far away as Karakisa, Severn, and Carmora. The construction, protection, and ongoing maintenance of these aqueducts are widely viewed as one of the finest examples of Viridian engineering, having been in use nearly continually since they were first built in the early years of the Reign of Light.
Many small communities and one larger city - Synnada - line the shores of Lake Caanthus.