Sorpe Reservoir, Reservoir in Hochsauerlandkreis, Germany

Sorpe Reservoir is the artificial lake held back by the Sorpe Dam, a concrete gravity dam about 700 metres long and up to 69 metres high, built 1926–1935 in the Sorpe valley near Sundern. Its downstream face is divided by three vertical piers into two outlet bays that release water into a basin below; a sloped bank of pale riprap meets the dam on the left.

Between 1926 and 1935, the reservoir was built, with construction materials transported via the Röhrtal railway. The construction site was considered one of the largest in Europe at the time and employed hundreds of workers.

The reservoir is run by the Ruhrverband in Essen, which manages eight dams in the region. Its water is released into the Sorpe and the Ruhr to raise low-water levels for drinking-water works downstream. A small power station at the dam foot uses two Francis turbines and a Kaplan turbine, producing 11.5 GWh a year on average.

The western shore offers several campsites and holiday homes, while the eastern bank is less developed and provides quiet hiking trails. The grassy areas by the water are good for breaks, and small coves invite visitors to linger.

The dam was attacked twice in World War II and held: in 1943 during Operation Chastise, and on 15 October 1944, when ten Tallboy bombs dropped by Lancaster bombers caused little damage. In 1958, while the reservoir was emptied for repairs, workers found an unexploded bomb; Langscheid was evacuated on 6 January 1959 before it was defused.