The River Exe rises near the village of Simonsbath, on Exmoor in Somerset, near the Bristol Channel coast, but flows more or less directly due south, so that most of its length lies in Devon. It reaches the sea at a substantial ria (estuary) on the south (English Channel) coast of Devon. Historically, its lowest bridging point was at Exeter, though there is now a viaduct for the M5 motorway about 3 km south of the city centre. The river fuelled Exeter's growth and relative importance in medieval times and the city's first industrial area was developed at Exe Island, created by a series of leats to the west of the city. The island was home to numerous mills producing paper and textiles, and also created valuable land through drainage of the marshlands. The river's name is obviously related to that of Exeter, and in addition many villages along the course of the river take their names from it, including Exford, Up Exe, Nether Exe, Exwick, Ex