With a length of 80 kilometres (50 mi), it is New Zealand's longest lake, and, at 291 km2 (112 sq mi), its third largest. The lake is also very deep, its floor being as low as 100 metres (330 ft) below sea level, giving it a depth of between 378 metres (1,240 ft) and 420 metres (1,380 ft) making it New Zealand's third or fourth deepest lake and ranked 32nd deepest in the world, putting it just behind Lake Hauroko 462 metres (1,516 ft), Manapouri 444 metres (1,457 ft), and possibly Te Anau 418 metres (1,371 ft) and Hāwea 392 metres (1,286 ft). It is at an altitude of 310 metres (1,020 ft), towards the southern end of the Southern Alps. The general topography is a reversed "N" shape or "dog leg". The Dart River flows into the northern end, the lake then runs south for 30 kilometres before turning abruptly to the east. Twenty kilometres (12.4 mi) further along, it turns sharply to the south, reaching its southern end 30 kilometres (19 mi) further south, near Kingston.
The lake is drained by the Kawarau River, which flows out from the lake's Frankton Arm, 8 km (5.0 mi) east of Queenstown. Until about 18,000 years ago the Mataura River drained Lake Wakatipu. The Kingston Flyer follows part of the former river bed now blocked by glacial moraine . Queenstown is on the northern shore of the lake close to eastern end of its middle section. It has a seiche of period 26.7 minutes which, in Queenstown Bay, causes the water level to rise and fall some 200 millimetres (7.9 in).
Lake Wakatipu is renowned for its scenic beauty, being surrounded by mountains. The Remarkables mountain range lies along its southeastern edge. It is a popular venue for adventure tourism, with skifields, paragliding, bungy jumping and tramping tracks within easy reach. A vintage steamboat, the TSS Earnslaw regularly plies its waters. Several vineyards are nearby in the Gibbston Valley.