Bilzbad

The Bilzbad lies at Meiereiweg 108 in the Kötzschenbroda Oberort district of Radebeul in Saxony, just above the Lössnitzgrund valley and close to the Lössnitzgrundbahn halt. The naturopath Friedrich Eduard Bilz, author of the four-volume Bilz, das neue Naturheilverfahren, bought some nine hectares of land from 1903 and opened the site on 25 June 1905 as the Bilz-Licht-Luft-Bad, an air-and-light bath meant to spread his natural-healing doctrine and to serve as a public health resort affordable to anyone. His own prospectus argued that daily air baths store health in the body, harden it and cheer the spirit. The complex grew to roughly thirty hectares and by 1907 already had three water basins; his youngest son Willy Johannes Bilz and his wife Margarete Ottilie ran it from 1906.

The bath's distinguishing feature arrived in 1912. Bilz saw a wave basin at the First International Hygiene Exhibition in Dresden in 1911, bought it at once, and had the Undosa wave machine installed on 28 June 1912, after which the venue was also known as the Undosa-Wellenbad. A bell announced each hourly wave cycle. German Wikipedia, used here as a second source, records that this 1912 machine is the oldest wave machine of its type and is described in the Saxon monument database as singular, that it is a listed technical monument and still in operation, and that the bath is probably the world's oldest still-operating wave bath working in its original manner, marking a century of service in 2012. Two objects are separately listed: the former eastern entrance building on the Meiereiweg, which now houses the Bilz museum, and the open-air bath itself with its still regularly used wave machine. Museum and the restaurant in the former service building are open to the public without paying bath admission.

Ownership passed from the family to the city of Radebeul in 1975, when Hans-Joachim Bilz had to sell at what Wikipedia's source calls a minimal price; the bath is public property today and is run by the Stadtbäder und Freizeitanlagen GmbH Radebeul, an independent municipal company. The much-reduced bathing enclosure south of the Meiereiweg was thoroughly rebuilt between 1992 and 1998, the Undosa machine included; a modern motor now drives the historic flywheel through a leather belt, and a metal wave box replaced the original wooden one in a 1998 reconstruction, with the original preserved. A new non-swimmer pool opened in 2012 in place of the Inselbad, which had been closed as unsound, and a traceboarding line was added in 2016. Some 49,000 people visited in 2015.

Today's operation is a seasonal open-air bath with an attached campsite, event hire and a leased catering area. There is no thermal, mineral or brine water and no indoor bathing or sauna: the water is ordinary treated bathing water, and the operator's pages nowhere use the words Thermalwasser, Heilwasser, Sole or Mineralwasser. Bathing hours are 10:00 to 18:00 in May and September and 10:00 to 19:00 from June to August, with last admission an hour before closing; the 2026 season closed on 6 September, while the campsite stayed open to 31 October. Summer events continue the Bilz tradition, including the Bilz-Bad-Fest organised since 1992 by the Bilz-Bund association and a beach volleyball tournament, the Bilz-Beach-Cup.