The Balkan Lake Ohrid (40°54' to 41°10' N, 20°38' to 20°48' E) is the most outstanding ancient lake in Europe. It is 30.3 km long, 15.6 km wide, covers an area of 358 km² and is located at an altitude of 693 m a.s.l. The lake has a relatively simple tub-shaped basin morphology with a maximum water depth of 286 m. A complete overturn of the entire water column occurs approximately once every seventy years.
The lake harbors an incredible biodiversity with a large number of endemic species. Taking lake size into account, it belongs to the most biodiverse lakes in the world.
The oligotrophic state and the high degree of endemism make Lake Ohrid a natural treasure for Albania and Macedonia. Increasing anthropogenic impact during the past decades such as tourism, fishing, and growing industrial and agricultural activity in the catchment, is, however, leading to eutrophication and jeopardizes this unique ecosystem.
Wagner, B., Wilke, T. & Brovkin, V. (eds.), 2011: Evolutionary and geological history of Balkan lakes Ohrid and Prespa. Biogeosciences, Special issue, Copernicus Publications, Göttingen
Albrecht, C. & Wilke, T., 2008: Ancient Lake Ohrid: biodiversity and evolution. Hydrobiologia 615: 103–140
Noveska, V., Naumoski, T., Gjorgonoska, D. & Mitic, V., 1985: Bibliography for Lake Ohrid. Special edition. Ohrid: 1–42
Stankovic, S., 1960: The Balkan Lake Ohrid and its Living World. Monographia Biologicae, Vol. IX. Uitgeverij Dr. W. Junk, Den Haag 357 pp.