This reservoir was the second of three to be built in the northern section of the Upper Derwent Valley. The three lie within the Peak District National Park. Derwent is 2 km (1.5 mi) in length and was historically used by pilots practising for the ‘Dam Busters’ raids during World War II. The land surrounding it is woodland, moorland and open hills, and the latter is used by local sheep farmers for grazing. Activities include walking along the footpaths that criss-cross the moorland and bird watching. A cycle route runs round the three reservoirs and there are bridleways for horse riding.