Lake Taupo (616 sq km, 185m deep) is itself a geological infant largely created in 186 AD when the Taupo Volcano spewed out 24 cubic kilometres of rock, debris and ash – at least ten times more than was produced by the eruptions of Krakatoa and Mount St Helens combined – and covered much of the North Island in a thick layer of pumice. Ash from the eruption was carried around the world – the Chinese noted a blackening of the sky and Romans recorded that the heavens turned blood-red. As the underground magma chamber emptied, the roof slumped, leaving a huge steep-sided crater, since filled by Lake Taupo. It’s hard to reconcile this placid and beautiful lake with such colossal violence, though the evidence is all around: entire beaches are composed of feather-light pumice which, when caught by the wind, floats off across the lake. Volcanologists continue to study the Taupo Volcano (currently considered dormant) and treat the lake as a kind of giant spirit-level, in which any tilting could indicate a build-up of magma below the surface that might trigger another eruption.
The local Tuwharetoa people ascribe the lake’s formation to their ancestor, Ngatoroirangi, who cast a tree from the summit of Mount Tauhara, on the edge of Taupo, and where it struck the ground water welled up and formed the lake. The lake’s full name is Taupo-Nui-A-Tia, “the great shoulder mat of Tia” or “great sleep of Tia”, which refers to an explorer from the Arawa canoe said to have slept by the lake.