The water comes from the underground lake, some 30,000 thousand years old. Water is beneficial for the rheumatic and cardiac illnesses, when properly used (being still in the water and no more than three times a day with total of 20 minutes only). Just outside of the complex is another water spring ("third water", the Rzav and the spa being the first two). It allegedly helps with the eye diseases. The intake for the spring was built in 1975. Local ecologists opted not to place garbage bins, instead all visitors take garbage back with them.