Mt Hobson/Ohinerangi Volcano

BY BRUCE HAYWARD (GEOLOGIST)
Accessibility: MODERATE
Mt Hobson scoria cone
Mt Hobson is one of Auckland's most prominent volcanic cones.
View of Mt Hobson from the Southern Motorway heading south over the Newmarket Viaduct.
Mt Hobson is one of the 53 small volcanoes in the Auckland Volcanic Field, all of which erupted in the last 200,000 years. It consists of a tall scoria cone (summit 143 m above sea level) formed by fire-fountaining of frothy lava from its crater. The crater is horseshoe-shaped because it has been breached by a lava flow that flowed both north and south from the cone approximately along the present route of the Southern Motorway.
Mt Hobson Domain was gazetted in 1880 and the northwestern slopes added to the reserve by donation by the Dilworth Trust.
Mt Hobson houses two buried water reservoirs - one on the crest and one in the floor of the crater where a US mobile hospital was built during World War 2.
Panoramic views of the harbour and Devonport volcanoes from the summit.
Why is some of the top of the scoria cone perfectly flat?
When originally formed the scoria cone slopes were smooth - why do some of them have terraces and ditches and pits on the top?
Why is the crater open on one side?
Directions/Advisory

Walking access from gates on Remuera Rd, Dilworth Ave and Mt Hobson Rd.

Grassed steep slopes can be slippery, especially when wet.

Google Directions

Click here for Google driving directions

Accessibility: MODERATE

Best walking tracks are from the two gates on Remuera Rd with formed track to the top. Other access points require you to walk up grassed slopes of cone.

Features
Matauranga Maori
Geological Age
Erupted about 34000 years ago.
Links
Hayward, B.W. 2019. Volcanoes of Auckland: A field guide. Auckland University Press: p.124-127. https://aucklanduniversitypress.co.nz/volcanoes-of-auckland-a-field-guide/ Hayward;B.W.;Murdoch;G.;Maitland;G.;2011. Volcanoes of Auckland: The Essential Guide. Auckland University Press.p. 132-133.;