The Derwent is a river in Derbyshire, England. It is 50 miles (80 km) long and is a tributary of the River Trent, which it joins south of Derby. Throughout its course, the river mostly flows through the Peak District and its foothills. The scenery of the Derwent valley attracts many tourists. The upper reaches pass through the Peak District National Park, whilst the middle reaches around the old spa town of Matlock Bath offer souvenir shops and amusement arcades, together with attractions such as the Heights of Abraham and its cable car.