Drilling oil at 1830 meters, employees of the Croatian oil company found hot water (96° C) in 1967. The water is salty and extremely rich in minerals, and is warmer than any other known thermal water. The second geothermal spring is shallower (1650 m) and the water is not so hot (85° C) although it is almost identical in composition, it is clearer than the water from the first spring. Water exploitation began immediately. People bathed in the drains.
As early as 1974, an outdoor swimming pool was built and an accommodation facility next to it. This hotel had a restaurant, and an outdoor and indoor pool. Hotel "Termia" was opened in 1990, and within it the Polyclinic for Medical Rehabilitation. In 1997, the construction of Aquapolis, a modern bathing complex with 9 pools and 1500 m2 of water surface with a semi-Olympic pool, non-swimmer pool, children's pool, pool with water attractions, music cave and whirlpools, three jacuzzi pools of different sizes and depths with large mushroom fountain and artificial waterfall.
In winter it is an indoor, air-conditioned and ideally heated entertainment and recreation area, while in summer it is a real riviera that receives approximately 6000 bathers.