Tongariro National Park
Volcanic processes have been building the mountains of Tongariro National Park for over two million years. Three volcanoes (Tongariro, Ngauruhoe and Ruapehu) remain active, while the park's two northernmost volcanoes (Pihanga and the Kakaramea-Tihia Massif) last erupted over 20,000 years ago. They have however produced significant historic mudflows.