Abandoned Mine production of white calcite (Russia)
Dugin's quarry (Russia)
Development of Dugin's quarry opened by various sources around the 16th century. Extensive network of tunnels used for the extraction of limestone used for construction of the "White Moscow." The length of the quarry is estimated at about 5,500 meters. Now a vast network of tunnels has become one of the most popular routes spelestologicheskih.