or less continuously. From the 8th to the 12th century the region around the Plöner See was settled by Slavs. There is still evidence of this in the Olsborg, an island south of Plön, that was heavily fortified. The Slavs called it Plune, which meant "ice-free water". In 1139 the Holstein count Adolf II of Schauenburg destroyed the fort and ended Slav rule over the Plön region. Economic use The lake area is divided amongst several private owners as well as the state of Schleswig-Holstein. About 900 ha of the lake is rented out until 2020. The lake is fished by several professional fishermen. Species of fish include eel, perch, bream, pike, tench, carp, whiting, and whitefish. Tourism and leisure facilities The lake and its surroundings are a popular recreational area for residents of the metropolitan areas of Kiel, Lübeck, and Hamburg as well as a centre of tourism within Holstein Switzerland. There are a total of 15 bathing sites. Some campsites (including Bosau and Ruhleben) are located directly on the lakeshore. There is a wide range of recreational activities such as boating, sailing, diving, and fishing. During the summer pleasure boats ply the lake. Fishing In order to make the Holsteinische Schweiz fishing area more attractive to tourists, the fishing licensees have decided to combine their leases into a single guest fishing permit with which you can fish the entire lake area. The responsible authority is the Landessportfischerverband Schleswig-Holstein e.V. In summer, you can also fish at night for an additional fee. Boat rentals can be found in Plön. Of course, there are also plenty of slipways on the shores for those who want to use their own boat for fishing at Großer Plöner See. See also List of lakes in Schleswig-Holstein List of lakes in Germany References Sources Muuß, Uwe; Petersen, Marcus; König, Dietrich (1973). Die Binnengewässer Schleswig-Holsteins. 162 pp., numerous photos, Wachholtz-Verlag Neumünster. External links Environmental report on the Plöner See by the state of Schleswig-Holstein Tourism on the Plöner See Boating map Nature reserve law: "Inseln im Großen Plöner See und Halbinsel Störland Nature reserve law: "Ascheberger Warder im Großen Plöner See Ploner See, Grosser Nature reserves in Schleswig-Holstein LPlonersee, Grosser Plön