Tajchy - water reservoirs have a special place among the technical monuments in Banská Štiavnica and the surrounding area. The first efforts to build artificial water reservoirs in Banská Štiavnica region date back to the 15th and 16th century. In the first half of the 18th century due to existing problems in mining works and its large-scale construction, the creation of a mine water management system was began, which made it possible to pump out mine water, and at the same time, mine pumping technology was developed, which was a model for other mining regions. The important constructor, inventor Jozef Karol Hell and cartographer Samuel Mikovíni were mainly responsible for building the entire system. In the past, almost 60 water reservoirs were built in Banská Štiavnica region, of which only 24 have been preserved and are used for recreation. The existence of water reservoirs and the water management system was one of the reasons why Banská Štiavnica was included in the UNESCO World Natural and Cultural Heritage List.