From the crater of the extinct millions of years ago volcano “Kozhukh” spring thermal waters with a temperature of about 74 ° C, which are known for their healing properties throughout Bulgaria. Actually, not exactly from the crater, but from rocks from a deep fault zone formed at the end of the Paleocene geological epoch. The volcano Kozhukh is embedded in these rocks from the same epoch. The healing mineral water of Rupite is characterised by its content as highly mineralised, hyperthermal, bicarbonate, sodium, fluorine and silica. In terms of chemical composition, it contains certain amounts of the trace elements aluminium, arsenic, copper, lead, selenium, zinc, barium, boron and cyanides.