 It flows from Burnside, near the border with Perth & Kinross, then slowly across the Howe of Fife (until drained in the 18th and 19th centuries a flat and waterlogged basin) and through the market town of Cupar to Guardbridge, where it enters the North Sea via the Eden Estuary, an important conservation area for wading birds and a nature reserve.The river holds a good stock of wild brown trout and hosts a fair run of sea trout and Atlantic salmon.In previous centuries, its water was used to power mills on its banks, and there was a paper mill at Guardbridge until July 2008.