Lake Hévíz is located in the western part of the country, not far from the southwestern end of Lake Balaton. Lake Hévíz is the largest lake of thermal water in the world, in which swimming is possible, both in terms of temperature and chemical composition. Lifeforms that dominate the lake are bacteria and algae. Several species of bacteria can be found only in this lake, and more of them are very rare. Water is curative for rheumatic diseases, and locomotor disorders, so it is not surprising that medical tourism is in expansion on this beautiful lake.