Forggensee is a lake located north of Füssen in the district of Ostallgäu in Bavaria, Germany. One of many lakes in the region around Hohenschwangau and Neuschwanstein castles, Forggensee is the fifth-largest lake in Bavaria, with a surface area of 15.2 km². The River Lech flows through it. Forggensee is known primarily as a tourist destination for aquatic sports and recreation. The lake provides ideal conditions for surfing, sailing, fishing and boating. The lake is stocked with pike, trout and eel. Two ships navigate the lake on two different routes.
Forggensee is a man-made lake. It was created in 1954, when the River Lech was dammed for the first time to create the Lechsee Lake. The option of letting water in and out reduces the risk of flooding when the snow melts in the spring and regulates the flow of water over the "Power Plant Step" located downstream.