The centuries-old history of Kyustendil is closely connected with its curative mineral springs which initially attracted the Thracian tribes; after that, the Romans built the second-largest balneological healing temple in the Balkans here in Pautalia in honour of the God Aesclepion, to which the many remains of Roman thermal baths bear witness. Within the town there are about 40 mineral springs with a water temperature of +73o C and a debit of 33 l/s. It has a low level of mineralization (719 mg/l) with a high level of alkalinity – pH 9.15. The water has proven curative quality for a number of illnesses; gynecological, male and female sterility, neurological and skin diseases, diseases of the respiratory system, the musculoskeletal structure, various job-related illnesses etc. Together with mineral water treatments, procedures with mud are also carried out in Kyustendil. The curative peat, rich in different minerals and organic substances, is drawn from a peat source near Baykal Village which has been preserved for medicinal uses. Highly-qualified specialists with years of experience in balneology care for visitors to the town in well-equipped centres for rehabilitation and public bathhouses.