Ōtsu, capital, Shiga ken (prefecture), southern Honshu, Japan, on the shore of Lake Biwa. A castle town established by Toyotomi Hideyoshi in the 16th century, it is situated at the junction of ancient highways, including the Tōkaidō (Eastern Sea Highway). Ōtsu has long been a gateway to Kyōto and a centre of transportation. The city contains the Ishiyama-dera (Ishiyama Temple), associated with Murasaki Shikibu, author of the 11th-century novel Genji monogatari (The Tale of Genji), one of the great classics of Japanese literature. Industries produce electrical appliances and textiles. Pop. (2005) 323,719; (2010) 337,634.