Gosetal to a depth of 500–600 metres. At the end of January 2010, after a news blackout of several months, the company announced that they would soon be drilling to a depth of 800 metres, where they suspected there would be rich mineral deposits. World Heritage Site In 1992 the museum became a UNESCO World Heritage project together with Goslar's Old Town. In 2010 this World Heritage Site was expanded to include the Upper Harz Water Regale, Walkenried Abbey and the historic Samson Pit. The Rammelsberg Museum and Visitor Mine is an anchor point on the European Route of Industrial Heritage (ERIH). The World Heritage Site protects many artifacts from the medieval era of mining operations at the mountain, including: old pithead dumps and slag heaps (the oldest dating from the 10th century) ore transportation tracks dating from the 12th century the Roeder Gallery (with a flatrod system and several water wheels that support the drainage of the pit and the hoisting of ore; there is a replica in the Deutsches Museum in Munich) the Feuergezäher Vault (the oldest "nogged" (ausgemauert) underground mining space in Central Europe) the Rathstiefste Gallery (medieval drainage adit; decorated with coloured vitriol encrustations) the headframe (18th century) the Master Malter's Tower (Maltermeisterturm) (oldest above-ground mining building in Germany) Mine installations Master Malter's Tower The Master Malter's Tower (Maltermeisterturm) is the oldest surviving above-ground mine building on the Rammelsberg and, probably, in Germany as well. It was built around 1500 on a slagheap on the side of the Rammelsberg. Initially the tower was used to oversee the pits; from 1578 it was used as a bell tower (Anläuteturm). Since the mid-18th century the master malter (Maltermeister) lived in the tower. He managed the wood needed for the mine, which was measured in malters, hence the name. Herzberg Pond In order to have enough water to drive water wheels during times of drought the Herzberg Pond was created in 1561. Since 1926, this has been used as a woodland swimming pool. Until the closure of the mine, water was used for cooling and the warm water was pumped back into the pond where it heated the swimming basin of the woodland pool. Low-grade ore dressing on the Bollrich Due to the German Wirtschaftswunder ("economic miracle") after the Second World War and sharply rising lead and zinc prices in 1950, investigations were undertaken into the deposits of banding