The Kurhaus is a venue located at the western end of the park, at the foot of the castle ruins in Badenweiler, a small town nestled in the western edge of the Black Forest in south west Germany. The foundation stone of the original Kurhaus was laid in 1851, and by 1853 the building was in use as a pump room and gathering place. That same year the building began to be used as a venue for concerts.
With increasing visitor numbers the demand for the thermal waters grew, and in 1863/4 the source was reviewed and then considerably enlarged with excavations. In 1965 the public baths administration tapped additional spas in the park, and by 1972 Badenweiler became established as a spa resort.
The new Kurhaus was opened the same year. It is an imposing multi-storey building with asymmetric terraces, promenades, and planted areas. Architecturally it seeks to mirror in virtual form the park in which it sits, and opens up additional areas in which the visitor can lounge.
In addition to an open-air theatre, the facilities within include an auditorium, a comfortable theatre, a spacious foyer, and corridors that draw their inspiration from forest paths. The Kurhaus also hosts the "Chekhov Salon" Literary Museum, an exhibition of the life and work of Russian author Anton Chekhov, who died in Badenweiler in 1904, and whose bust can be encountered along the path that winds around the base of the castle ruins.
Source: http://www.badenweiler.de/de/sehenswuerdigkeiten/kurhaus (German)