At its greatest extent, which is roughly along a north–south axis, the lake is 42 kilometres long. Its widest point, at the southern end, is 10 kilometres. The lake's western shore is lined with high peaks rising to over 2000 metres above sea level. Along the eastern shore the land is also mountainous, but the peaks are somewhat lower. 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 Matukituki and Makarora Rivers, and is the source of the Clutha River. Nearby Lake Hāwea lies in a parallel valley carved by a neighbouring glacier eight kilometres to the east. At their closest point, the lakes are only 1,000 metres apart. Small islands towards the foot of the lake include Ruby Island, Stevensons Island and Harwich Island. Some host ecological sanctuaries, such as one for buff weka on Stevensons Island. The towns of Wanaka and Albert Town are near the lake's outflow into the Clutha River.
Climate
Human history
Exploration and settlement
For Māori, the Wānaka area was a natural crossroads. The Haast Pass gave access to the West Coast and its pounamu; the Cardrona Valley led to the natural rock bridge "Whatatorere", which was the only place that the Kawarau River and Clutha River / Mata-Au could be crossed without boats. Native reeds were used to build boats that enabled a swift return downriver to the east coast. The Cromwell basin supported a large population of moa, which were hunted to extinction about 500 years ago. Until the early nineteenth century, Wānaka was visited annually by Ngāi Tahu who sought pounamu in the mountains above the Haast River and hunted eels and birds over summer, returning to the east coast by descending the Clutha River / Mata-Au in reed boats. According to the Ngāi Tahu, Lake Wānaka was dug by the Waitaha explorer Rākaihautū with his kō named Tūwhakaroria. After Waitaha arrived in the Uruao waka at Whakatū, Rākaihautū divided his people into two groups. Rākaihautū led his group down the middle of the island, digging the freshwater lakes of Te Waipounamu. Numerous kāinga mahinga kai and kāinga nohoanga were located around the lake. The Kāti Māmoe settlement as the site of modern Wanaka was named Para karehu. The area was invaded by the Ngāi Tahu in the early 18th century. Ngāi Tahu use of the land was ended by attacks by North Island tribes. In 1836, the Ngati Tama chief Te Puoho led a 100-person war party, armed with muskets, down the West Coast and over the Haast Pass: they fell on the Ngāi Tahu encampment between Lake Wānaka and Lake Hāwea, capturing 10 people and killing and eating two children. Although Te Puoho was later killed by the southern Ngāi Tahu leader Tuhawaiki, Māori seasonal visits to the area ceased. The first known map of Lake Wānaka was drawn in 1844 by the southern Ngāi Tahu leader Te Huruhuru. The first European to see the lake was Nathaniel Chalmers in 1853. Guided by Reko and Kaikoura, he walked from Tuturau to the lake via the Kawarau River. However he was stricken by dysentery, so his guides returned him down the Clutha in a reed boat. By 1861, several sheep stations had been established in around the south end of the lake, and in 1862, the lake itself was surveyed in a whaleboat. The early European name was Lake Pembroke.
Current use and tourism
In addition to ongoing sheep farming, the lake is now a popular resort, and is much used in the summer for fishing, boating and swimming. The nearby mountains and fast-flowing rivers allow for adventure tourism year-round, with jetboating and skiing facilities located nearby. With Queenstown airport close by, tourism mirrors that of the surrounding areas.
Conservation
As one of the few lakes in the South Island with an unmodified shoreline, the lake is protected by special legislation, the Lake Wanaka Preservation Act of 1973. The Act established a 'Guardians of Lake Wanaka' group, appointed by the Minister of Conservation, which advises on measures to protect the lake. Oxygen weed, an aquarium plant and invasive species native to Southern Africa, has been a problem in the lake's ecosystem for some time. Attempts to eradicate the weed have not been successful. Substantial suction dredging operations have shown promise, but tend to miss isolated spots which then regrow into larger weed beds.
In popular culture
"That Wanaka Tree" – a willow growing just inside the lake – is a tourist attraction in its own right, featuring on many tourists' Instagram feeds. The tree had its lower branches cut by vandals in 2020. The lake is referenced in the title of the song Lake Wanaka by Israeli singer-songwriter Keren Peles.
In film
The region has been the setting for many international films, including The Lord of the Rings, The Hobbit, the Legend of S, and A Wrinkle in Time. Lake Wānaka was mentioned several times in the movie as a location the lead couple visited and as the answer to Ethan Hunt's question on the phone to verify the identity of his wife. The New Zealand cook and author Annabel Langbein, who owns a small estate at the side of the lake, filmed her series The Free Range Cook and Simple Pleasures here.
As a reported refuge
New Zealand has been reported to be a favoured refuge for the 'super rich' in the event of a cataclysm. One such high net worth individual is Peter Thiel, who purchased of lakeside land in 2015, although he had not developed it as of 2020.
