The salt mines of Wieliczka, Polish Kopalnia soli Wieliczka salt mines are located in Wieliczka near Krakow, Poland in 1978 and listed on the World Heritage List of the United Nations Educational, science and culture
Exploited since the thirteenth century, they include nine levels and 300 km of galleries. As they are kept at a temperature of 14 degrees Celsius and cracks in the walls are checked and the components in the air to prevent explosions.
Mining ended in 1996, the heritage protection and development of tourism has become incompatible with it.
The salt formation is geologically composed of evaporite Miocene strata.