Until the mid-19th century, the three tallest dams in Europe built for the mining industry had been tajchy in Slovakia: Rozgrund (30.2 m), Počúvadlo (29.6 m), and Veľká Richňava (23.4 m). In the same period, 7 out of 13 European mining water reservoirs with the biggest volume of water were tajchy. After several centuries, tajchy became an integral part of their natural environment. Several of the dams have been recently reconstructed. Some of the reservoirs are heavily frequented by tourists, while other, usually smaller lakes lie hidden in the forests of the Štiavnica Mountains.