75% of the track is within 3 km of Te Maari. The track is usually to windward of Te Maari as the prevailing wind is west to south west in this region. When mixed with rain the ash forms a gritty mud. In late November 2012 Te Maari crater again erupted an ash cloud 4,000m high over a 5-minute period. About 100 people were in the vicinity including a group of 20 13-year-old students from Gulf Harbour school but no one was injured. The crater is visible from the Ketetahi area. There are no tracks to Te Maari as it is an unstable, volcanically active zone. The Tongariro Alpine track was closed for 4 days but the other 12 tracks on the mountains were left open. Fumaroles remain active around the active rim of Te Maari crater and there is a strong smell of sulphur gas close to the rim. See also New Zealand tramping tracks Tongariro Northern Circuit References External links New Zealand Mountain Safety Council's Tramping Video Series: Tongariro Alpine Crossing Department of Conservation - Tongariro Alpine Crossing information Hiking and tramping tracks in Waikato Protected areas of Waikato Ruapehu District