The Széchenyi Medicinal Bath in Budapest (IPA: [seːtʃeːɲi], Hungarian: Széchenyi gyógyfürdő) is the largest medicinal bath in Europe. Its water is supplied by two thermal springs, their temperature is 74 °C (165 °F) and 77 °C (171 °F).
Components of the thermal water include sulfate, calcium, magnesium, bicarbonate and a significant amount of metaboric acid and fluoride.
During the planning phase from the 1880s, the bath had originally been referred to as the Artesian spa (Artézi fürdő), but when it opened on June 16, 1913, it was officially named Széchenyi spa after István Széchenyi.
The bath, located in the City Park, was built in Neo-Baroque style to the design of Győző Czigler. The pool construction cost approximately 3.9 million Austro-Hungarian korona. The total area covered was 6,220 square metres (67,000 sq ft). More than 200,000 bathers visited the spa in 1913. This number increased to 890,507 by 1919. At that time the Bath consisted of private baths, separate steam-bath sections for men and women, and male and female "public baths." The complex was expanded in 1927 to its current size, with 3 outdoor and 15 indoor pools. It is now possible for both sexes to visit the main swimming and thermal sections.
After the expansion, the thermal artesian well could not supply the larger volume of water needed, so a new well was drilled. The second thermal spring was found in 1938 at a depth of 1,256 metres (4,121 ft), with a temperature of 77 °C (171 °F). It supplies 6,000,000 litres (1,600,000 US gal) of hot water daily.[1] Between 1999 and 2009 the Széchenyi thermal bath was refurbished in a complete renovation.