channels were laid between the wall segments which had gradually disintegrated over time. As a result, vertical boreholes were drilled to drain the water away. The waterworks was modernised and supplies 2.9 million m³ of water annually. Since the overhaul and the aforementioned modifications, the crest is now open to walkers crossing the valley. The forestry commission has also removed trees blocking the view of the southern side of the dam from the observation point at Peterstein (checkpoint 36 on the Harzer Wandernadel hiking network). Recreation Swimming in the reservoir is forbidden in order to protect the fresh water. The reservoir is surrounded by a 4.5-km-long hiking trail. It can be reached from Drei Annen Hohne, Elbingerode or Wernigerode. A footpath leads to the nearby Peterstein mountain summit, from which there is a view over the reservoir. Trees that obscured the view were removed from the mountaintop during dam and reservoir renovation by the forestry commission. See also List of dams in the Harz List of reservoirs and dams in Germany Notes Dittmar Marquordt:Neuer Harzbote.Heft 5, Fremdenverkehrsverein Bodfeld/Harz, Elbingerode (Harz), 1999, S.175. Hugo Ehrt:Neuer Harzbote.Heft 13, Fremdenverkehrsverein Bodfeld/Harz, Elbingerode (Harz),2003, S.565. External links Zillierbach Dam Dam operations in Saxony-Anhalt Information on the rebuilding (pdf; 193 kB) Contemporary silent film about the construction of the Zellierbach Dam near Wernigerode (1934-36) Dams in Saxony-Anhalt Dams in the Harz Dams completed in 1936