Mount Ngauruhoe is an active stratovolcano or composite cone in New Zealand, made from layers of lava and tephra. It is the youngest vent in the Tongariro volcanic complex on the Central Plateau of the North Island, and first erupted about 2,500 years ago. Although seen by most as a volcano in its own right, it is technically a secondary cone of Mount Tongariro.The volcano lies between the active volcanoes of Mount Tongariro to the north and Mount Ruapehu to the south, to the west of the Rangipo Desert 25 kilometres to the south of the southern shore of Lake Taupo.
The mountain is usually climbed from the eastern side, from the Mangatepopo track. From the Mangatepopo hut to the base of the mountain takes a steady 1½ hour walk; the first 45 minutes are suitable for children or older people. The track then climbs very steeply to the base of the climb. In summer the climb is difficult due to the loose tephra that gives way underfoot. In the summer of 2010 a climber was seriously injured by falling rock.
Ngauruhoe erupted 45 times in the 20th century, most recently in 1977. Fumaroles exist inside the inner crater and on the rim of the eastern, outer crater. Climbers who suffer from asthma may be affected by the strong sulphurous gases emitted from the crater.
In 1974, as part of a promotional campaign for his sponsor Moët & Chandon, champion skier Jean-Claude Killy was filmed skiing down the previously unskied eastern slope of the mountain. The average slope on this side of the volcano is 35 degrees, and Killy was caught on radar skiing more than 100 miles per hour. In the early 2000s Mount Ngauruhoe was used as a stand-in for the fictional Mount Doom in Peter Jackson's The Lord of the Rings movie trilogy, achieving worldwide exposure.[