Mt Ruapehu information
Lonely Planet review
The multipeaked summit of Ruapehu (2797m) is the highest and most active of the park’s volcanoes, and the centrepiece of the national park, with Whakapapa Village (pronounced ‘fa-ka-pa-pa’), numerous walking tracks and three ski fields on its slopes.
The name means 'pit of sound', a reference to its regular eruptions. It began erupting over 250,000 years ago and remains active today, with major eruptions roughly every 50 years. During the spectacular 1995 eruptions, Ruapehu spurted volcanic rock and cloaked the area in clouds of ash and steam. From June to September the following year the mountain rumbled, groaned and thrust ash clouds high into the sky, writing off the 1996 ski season. The latest eruption, accompanied by a small earthquake, came out of the blue in September 2007, seriously injuring a climber sleeping in a hut on the mountain.
The mountain was the cause of one of NZ’s deadliest natural disasters. Eruptions in 1945 blocked the overflow of the crater lake, causing the water levels to rise dramatically. On Christmas Eve 1953 the dam burst and the flood of volcanic mud (known as a lahar) swept down the mountain and took out a railway bridge at Tangiwai (between Ohakune and Waiouru), just moments before a crowded express train arrived. The train was derailed and 153 people lost their lives.
The crater lake was blocked again by the 1995–96 eruption. As the levels rose, it was foreseen that a major lahar could lead to another catastrophe. Alarm systems were set up at the crater lake’s edge and in March 2007 they were triggered when a moderate lahar swept down the Whangaehu Valley. No one was injured and there was little damage to infrastructure.