The first spa and recreational establishments in the Crimea emerged during the economic boom at the end of the 19th century. The trend increased in the 20th century. So-called "sanatoriums", or health and beauty resorts, offered a wide variety of health-improving treatments. As the postcard shows, there was for example the option of taking a mud or moor bath. The thick, mineral-rich mud was believed to stimulate blood circulation and to have a positive effect on the immune system and the metabolism.
Nurses giving women mud baths at Saki sanatorium in Evpatoriia in Russia, black-and-white postcard, ca. 1920, unknown photographer; image source: National Library of Medicine, Images from the History of Medicine, http://ihm.nlm.nih.gov/luna/servlet/s/l327m3, public domain.