Lake Taupo in the North Island
Lake Grassmere
I don't know the answer, but I'd think Lake Te Anau would be in the top three, with its large fiord-like arms.
Lake Rotorangi
Lake Taupo, in the middle of the north island.
The Waikato is the longest river in New Zealand, running for 425 kilometres through the North Island. It rises in the eastern slopes of Mount Ruapehu, joining the Tongoriro river system and emptying into Lake Taupo (New Zealands Largest Lake).
lake coleridge
Since the length of a strait is rather indeterminate, there will be no exact answer. But Cook Strait would be longer than Foveaux strait. Are there others?
Lake Supereior is the longest lake in the US.
The average elevation for Queenstown New Zealand is 520m but the town centre is beside Lake Wakatipu which sits at 310m, it's New Zealands longest lake and is also the 3rd largest, at its deepest point it reaches 10m below sea level, that's a total of 420m deep.
Kiwi
Lake Tanganyika is the worlds longest lake and it is in Africa, in the country of Tanzania.
Lake Malawi is the longest freshwater lake in Africa.