The "Westernkottener Warte" brine spring, tapped at a depth of 78 meters in 1845, originated from an original search for rock salt. Surprisingly, this rich brine spring came to light, its water rising up in a striking fountain. Originally used primarily for salt extraction and also for medicinal purposes until 1949, the founding of Solbad Westernkotten GmbH in 1950 marked a significant transformation of the town. Since then, the brine, with a salt content of 8.1 percent, which is considered ideal and is rich in sulphate, calcium and hydrogen carbonate ions, has been used exclusively for therapeutic purposes. It is used for bathing and open-air inhalation at the Gradierwerke to promote and maintain health. In particular, the brine provides relief for diseases of the musculoskeletal system, such as rheumatic complaints. The aerosols from the Gradierwerk also have a beneficial effect on the respiratory tract by moistening it and helping to clear mucus, which is similar to a maritime climate.