Auckland Underground: The hidden lava cave
Where: Mt Albert
What: Lava cave
Age: 25,000 and 40,000 years, discovered in 2006
The Kitenui Avenue lava cave is a piece of Auckland's natural history, hidden in plain sight on a grassy suburban Auckland street.
The Mt Albert lava cave sits below the road and is only accessible through a rusty manhole in the berm – we're not telling you which one in case anyone is tempted to try to get in themselves.
It lay unknown to Aucklanders for tens of thousands of years until it was accidently discovered nine years ago.
Speleologist Peter Crossley said the cave was discovered in 2006 when "Mr Telecom or one of his mates" broke through the surface while digging a hole.
Auckland Council could not give anyone permission to go back into the cave because of the health and safety risks, Crossley said.
So one night he and a mate went into the cave to find out more.
The pair was running through the cave with "whoops of delight", he said, adding that "it was more crawling for most of it".
The cave stretched for 250 metres, and is considered one of Auckland's most significant lava cave finds in almost a century.
Crossley said he went back to the council the next day and they said: "Phew, we've been waiting for you to do that".
The cave, which was between 25,000 and 40,000 years old, was formed when the lava flow from the Mt Albert eruption made its way towards Point Chevalier.
When the "incandescent" lava drained away it left a donut-shaped cave.
Some parts of the cave were large enough to walk in and others barely left enough room to crawl.
Fewer then 100 people have ever been into the cave.
This means it's relatively clean, with just the roots of trees sprouting undisturbed through the roof.