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 Peipus the town. Near Kallaste, there is one of the largest surfacings of Devonian sandstone with a length of and a maximum height of , as well as several caves and one of the largest colonies of swallows in Estonia. Lake Peipus Lake Peipus (; ; ) is the largest transboundary lake in Europe, lies on the border between Estonia and Russia. The lake is the fifth-largest in Europe after Lake Ladoga and Lake Onega (in Russia north of St. Petersburg), Lake Vänern (in Sweden), and Lake Saimaa (in Finland). Lake Peipus represents a remnant of a body of water which