Upper Harz Ponds

The Upper Harz Ponds (German: Oberharzer Teiche) are found mainly around the mining town of Clausthal-Zellerfeld and the nearby villages of Buntenbock and Hahnenklee in the Upper Harz mountains of central Germany. There are around 70 ponds in total, both large and small. They were built by the miners of the Upper Harz, mostly between the 16th and 18th centuries, and are important components of the cultural monument known as the Upper Harz Water Regale - a network of dams, ditches, ponds and tunnels that was built to supply much-needed water power for the mining industry in the Harz mountains. Today the Water Regale is being proposed as a UNESCO World Heritage Site. About half the dammed ponds are classified today as reservoirs, but they have now become characteristic features of the Upper Harz and are home to some extremely rare plant and animal species.

The Upper Harz Ponds also have the oldest working dams in Germany.

The ponds were originally built for storing the water needed to drive the water wheels providing energy to the Upper Harz silver mines. These water wheels drove the pumps, the hoisting equipment, the stamp mills and, from 1820, the man engines as well.

To begin with, the ponds merely impounded water from their natural catchment areas. But in many cases, their inflow was later increased significantly through the use of additional collection ditches.

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