Lake Te Anau is in the southwestern corner of the South Island of New Zealand. The lake covers an area of 344 km2 (133 sq mi), making it the second-largest lake by surface area in New Zealand and the largest in the South Island. It is the second largest lake in Australasia by fresh water volume. The main body of the lake runs north-south, and is 65 km in length. Three large fiords form arms to the lake on its western flank: North Fiord, Middle Fiord and South Fiord. These are the only inland fiords that New Zealand has, the other 14 are out on the coast. Several small islands lie in the entrance to Middle Fiord, which forks partway along its length into northwest and southwest arms. The surface of the lake is at an altitude of 210 m. It has a maximum depth of 425 m, so much of its bed lies below sea level, with the deepest part of the lake being 215 metres below sea level.