비와 호
Lake Biwa, Japan's largest, is located at the center of this prefecture. It occupies one-sixth of its area. The Seta River flows from Lake Biwa to Osaka Bay through Kyoto. This is the only natural river that flows out from the lake. Most other natural rivers flow into the lake. There were many lagoons around Lake Biwa, but most of them were reclaimed in 1940s. One of the preserved lagoons is the in Omihachiman, and it was selected as the first Important Cultural Landscapes in 2006.