Tegernsee, lake, southern Bayern (Bavaria), southeastern Germany, lying at 2,380 feet (725 m) above sea level, surrounded by wooded mountains on the fringe of the Bavarian Alps, south of Munich. It is nearly 4 miles (6.5 km) long, almost 1 mile wide (1.6 km), and 3.5 square miles (9 square km) in area, with a maximum depth of 236 feet (72 m). Its waters discharge through the Mangfall to the Inn rivers. The lake is a popular summer and winter recreational area, with facilities for yachting and other water sports. Main resorts are Tegernsee village on the eastern shore, with the castle of the Bavarian king Maximilian I (until 1803 a Benedictine abbey, founded in 746); Bad Wiessee on the western shore, a spa with iodine and sulfur springs; and Rottach-Egern on the southern shore at the foot of the Wallberg (5,650 feet [1,722 m]), from whose summit are views across the Mangfall Mountains to the Hohe Tauern and of the Zugspitze, Germany’s highest mountain, to the southwest.