The Chiemsee, fondly called "Bavarian Ocean", is the largest lake in Bavaria and next to Lake Constance and the Müritz the third largest lake in Germany. It arose like many other alpine lakes at the end of the ice age as excavation of a glacier. Originally the lake was much larger and covered an area of almost 240 square kilometers, which is about three times the current water surface. The beautiful scenery around the lake is one of the most popular recreation areas in Bavaria. Most tourist marvel again and again at fascinating view of the nearby Chiemgauer mountains (Hochfelln, Hochgern, Hochplatte and Kampenwand) and visit the interesting islands in the lake. On the island Fraueninsel is convent of nuns and on the island Herreninsel are actually two castles and a landscaped park.