The Tagebau Hambach is a large strip mine (Tagebau) in Niederzier and Elsdorf, North-Rhine Westphalia, Germany. It is operated by RWE and used for mining lignite. Begun in 1978, the mine currently has a size of 33.89 km² and is planned to eventually have a size of 85 km². It is the deepest open pit mine with respect to sea level, where the ground of the pit is 293 metres (961 ft) below sea level.