Town (pop., 1995 est.: 14,000), Derbyshire Dales district, administrative and historic county of Derbyshire, north-central England. It consists of a group of settlements built along the River Derwent, in a region noted for its beautiful valleys and rugged hills. Between Cromford (site of Richard Arkwright's first water-powered mill in 1771) and the 16th-century Matlock Bridge, the river runs through a narrow gorge. The town was once a famous spa offering hydropathic treatment