Gellért Thermal Bath

Originally dubbed Sárosfürdő (mud bath) because of the layer of natural silt that settled at the bottom of the pool (back before it had a filtration system), Gellért Thermal Bath is now regarded as one of the city’s most opulent spas. There are several pools and steam baths ranging from a balmy 40°C (104°F) to a more bracing 19°C (66°F), but the indoor swimming pool, in particular, is a beautiful setting for a dip. Housed inside an Art Nouveau-era building, the pool is surrounded by ornate pillars and viewing balconies, while the expansive glass-panelled roof overhead affords the space plenty of natural light.