Lake Wānaka is New Zealand's fourth-largest lake and the seat of the town of Wānaka in the Otago region. The lake is 278 meters above sea level, covers 192 km2 (74 sq mi), and is more than 300 m (980 ft) deep.

"Wānaka" is the South Island dialect pronunciation of wānanga, which means "the lore of the tohunga or priest" or a place of learning.

Lake Wānaka lies in a u-shaped valley formed by glacial erosion during the last ice age more than 10,000 years ago. It is fed by the Mātukituki and Makarora Rivers, and is the source of the Clutha River / Mata-Au.

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