Csillaghegyi Open-air Baths is the oldest open-air bath in Budapest surrounded by a beautiful park. It started operation as early as the second half of the 19th century and has been operating in its present form since 2000. It is open even in winter, under a canvas tent roof. The open-air bath is built into the hillside in a terraced manner ; the swimming and beach pools can be found on the first level, while the children’s pool and the sun-bathing area are located uphill. The site has been converted into a park exceeding 90,000 m2. The 33-metre long swimming pool is filled with mineral water.