What Happened to Auckland's Lost Volcanoes?
Auckland has lost several of its volcanoes to quarrying and building. Cones like Mount Smart, Green Mount and Te Pou Hawaiki were dug away for their scoria and rock, and others lie buried under the suburbs. This is a big part of why the field's count varies between sources.
What happened to Auckland's lost volcanoes?
Many were quarried away or built over. Auckland's volcanic cones are made of scoria and basalt, which are valuable for roads, concrete and rail ballast, so for over a century the city literally dug up its own volcanoes for material. Others were levelled or buried as the city spread. The result is that several cones on old maps are now partly or entirely gone, which is why estimates of how many volcanoes Auckland has range from around 48 to 53.
Which volcanoes were quarried away?
Several of the most heavily worked are now hard to recognise. Mount Smart (Rarotonga) was largely quarried away, with the stadium now sitting in its remains. Green Mount (Matanginui) in East Auckland was almost entirely removed. Te Pou Hawaiki, a small cone near Maungawhau, was quarried and built over. Others like Mount Wellington, Three Kings and Wiri Mountain were partly cut into before protections came in.
Why were they quarried?
Because the rock was useful and close to hand. A growing city needs aggregate for roads, foundations and rail, and Auckland's scoria cones were a convenient local source sitting right where the building was happening. For decades that economic logic ran ahead of any sense of the cones as heritage. By the time their cultural and geological value was widely recognised, several had already been lost or badly damaged.
Can you still see any trace?
Sometimes, if you know where to look. A few quarried cones leave a stub, a cut face or an oddly shaped reserve that hints at what stood there. Others survive only as a name on a street or suburb. The contrast with the protected maunga like Maungawhau and Maungakiekie is stark, and it is a reminder of why the surviving cones are now so carefully looked after.
See the whole field, including what's left
Volcanic AKL maps every volcano in the Auckland field, the famous and the lost, with history and what remains today. Works offline on the maunga.
Explore Volcanic AKLRelated: How many volcanoes does Auckland have? and the volcanoes hiding in plain sight.