The well-known spa of Augusta (Hissar's ancient name) is situated in the centre of Bulgaria, in the Southern folds of Sredna Gora Mountain, 42 km North of Plovdiv (the second biggest town in the country) and 160 km East of Sofia (the capital of Bulgaria) in the Southern slopes of the Sredna Gora Mountains, close to the famous Valley of Roses.

The climate is moderate continental with mild and warm winter. The average annual snow cover is 12 days. Spring comes early, summer is temperately hot with an average month temperature of 22 C. Autumn is warm and long lasting. Cloud coverage is low. The average annual humidity is moderate (70 %). Foggy weather is an exception. The wettest months are June and November. The maximum air humidity is 65-70 %. Sunny days - 280 per year.

Today Hissar is a modern spa resort whose greatest asset consists in 22 mineral springs with a total debit of 4,000 l\min. and a temperature of 37-52 C, with a total exploitation flow of about 2,800 l/min. Hissar's mineral water is light, clear, colourless, flavourless and tasty. The radioactive emanation is 10-165 Em, pH - 7.6 - 9.02 and over 20 microelements. Acid content - 200 - 270 mg\l. It is slightly mineralised, hypo- and hyper-thermal, with a predominance of hydrocarbonic, sodium, sulphate and fluorine ions, as well as substantial amounts of radioactive gas characterized as slightly mineralised, hidrocarbonic-sulphate-sodium, with a high alkaline reaction (pH 8.3 to 9.02). Their temperature ranges between 27 Deg. C and 51 Deg. C and they vary in radioactivity, fluorine and metasilicic acid content. The water is mainly indicated for treatment of diseases of the kidneys and secretory system, liver and gall bladder, the digestive system and pancreas. Particularly good treatment results are achieved with comprehensive hydrotherapy and climatic cures, physiotherapy and kinesitherapy in cases of diseases of the kidneys and secretory system, such as a kidney stone, pyelonephritis, chronic nephritis and chronic renal insufficiency.

Excellent therapeutic results have also been achieved with the use of mineral waters for the treatment of diseases of the liver, pancreas, gall bladder and bile ducts. A very good effect is exerted on cholelithiasis by means of subaqueous intestine baths. Special comprehensive balneotherapy is also applied in a number of diseases of the digestive system - gastric and duodenal ulcers, chronic gastritis, colitis, some accompanying conditions of locomotory system, the endocrine system and the metabolism.