Lake Hévíz among Rotatorias as well ("Epiphanes brachionus" var. "Spinosus", "Lecane inermis"), which are only present in warm waters. Jenő Ponyi has described the lake's primitive crustaceans in detail. Also a unique "Hydracarina acarus" is said to have found its habitat outside the fence surrounding the lake. The waters are reported to be beneficial to patients suffering from rheumatic diseases and locomotor disorders, among others. There is a thriving health tourism industry in the area. Lake Hévíz Lake Hévíz is located in Hévíz, Hungary, near the western end of Lake Balaton, from Keszthely. It is the largest thermal lake in the world,
Lake Ladoga Lake Ladoga Lake Ladoga ( or ; [earlier in Finnish "Nevajärvi"]; ; ) is a freshwater lake located in the Republic of Karelia and Leningrad Oblast in northwestern Russia, in the vicinity of Saint Petersburg. It is the largest lake entirely in Europe, and the 14th largest freshwater lake by area in the world. "Ladoga Lacus", a methane lake on Saturn's moon Titan, is named after the lake. In one of Nestor's chronicles from the 12th century he mentions a lake called "the Great Nevo", a clear link to the Neva River and, possibly furthermore, to Finnish "nevo" "sea" or