Mt. Ruapehu

A hiker at the rim of Red Crater in New Zealand's Tongariro National Park.

Super Volcanoes: Hiking the Steaming Peaks of New Zealand’s Tongariro National Park

By Michael Lanza

We have just begun our all-day hike over some of the volcanoes of New Zealand’s Tongariro National Park when a trailside sign conveniently itemizes the life-threatening hazards awaiting us.

For starters, an eruption could eject large rocks into the air to rain onto us from the sky or release lava flows. Pyroclastic flows, which are clouds of ash, rock, and gas that can cook flesh, could come upon us at 60 mph. Just such a flow in 1975, in fact, formed the black rocks we’re standing on. Even short of a volcanic eruption, deadly volcanic gases can pool in the bottom of craters on calm, sunny days like today. And the rock on these peaks is so unstable that falling rock looms as a constant hazard.

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