Within 20km of the centre of Auckland there are fifty small volcanoes, but on the whole the city hasn’t been very respectful of its geological heritage. Even the exact number is hard to pin down, not least because several cones have disappeared over the last 150 years, mostly chewed away by scoria and basalt quarrying.
That might sound a Herculean feat, but Auckland’s largest volcano, Rangitoto Island out in the Hauraki Gulf, is only 260m tall, and in the city itself none is taller than Mount Eden, just under 200m. Many are pimples barely 100m high that only just poke above the surrounding housing. Early on, Maori recognized the fertility of the volcanic soils, and set up kumara gardens on the lower slopes, usually protected by fortified pa sites around the summit. Europeans valued the elevated positions for water storage – most of the main volcanoes have reservoirs in the craters.
It is only in the last few decades that volcanic features have been protected from development, often by turning their environs into parks – all or part of 37 of them have some form of protection. City ordnances dictate that some summits can’t be obscured from certain angles, and yet recently the edge of one volcano was only just saved from removal for a motorway extension. Some see UNESCO World Heritage Site status as the best means of protection, but it is unlikely anything will happen soon.
In the meantime, the volcanoes make wonderful viewpoints dotted all over the city, notably from Mount Eden, One Tree Hill, Devonport’s North Head and the top of Rangitoto Island where you can also explore lava caves.
The oldest volcanoes erupted 250,000 years ago, though it is only 600 years since the last eruption, and the volcanic field remains active. No one knows when the next eruption will be, but it is unlikely to be through one of the existing volcanoes – meaning one day a new peak will emerge.