The River Wye is a limestone river in the Peak District of Derbyshire, England. It is 22 miles long (widely but incorrectly attributed as 15 miles/24 km, which refers to the section within the National Park), and is one of the major tributaries of the River Derwent, which flows into the River Trent, and ultimately into the Humber and the North Sea. The main tributary of the river is the River Lathkill, which enters approximately one mile from its mouth.