The Cave That Was Sealed for Five Hundred Years

In the winter of 1889, workmen quarrying rock for the Sumner causeway on a Redcliffs hillside broke through a wall of earth and stones — and found themselves looking into a cave that had not been opened for five hundred years.

The hill had sealed it with a landslide. But inside, the last people who used it had simply walked out one day and never come back. There was no skeleton, nobody had died inside. Instead, there were the things a person leaves when they are sure they are coming home: a canoe paddle, carved and painted. A wooden bailer. A float for an outrigger canoe. Fishing nets. A small carved wooden dog, the kind kept as a companion. Bone bird-spear points by the dozen, adzes, fish-hooks, and heaps of cockle shells from the estuary at the bottom of the hill.

That pile of everyday possessions turned out to be one of the most important archaeological finds ever made in New Zealand. Some of those pieces are the oldest wood carvings in the South Island, a thousand years of decay had not touched them, because the landslide had sealed the cave like a jar. Archaeologists now date the occupation to around 1400, the very end of the time when people still hunted moa. Even the moa bones inside had been worked into tools, not cooked. There was enough evidence to help pin down one of the great questions of the country's prehistory: the moa, it now seems, survived barely a century or two after the first people arrived.

Here's what makes the site so strange. A few hundred metres away sits the cave's mirror image — Te Ana o Hineraki, Moa Bone Point Cave, a shelter that stayed in use for six hundred years, right through to the 1840s, dug over by the famous geologist Julius von Haast in 1872. Same cliff, same coast, same food on the same flats. One cave was lived in until the memory of the land ran out; the other was sealed at 1400 while its owners were out fishing, and the hill kept their things warm for half a millennium.

The site today is closed to walkers, the cave mouth has been fenced since the 2011 earthquakes, in case the same cliff lets go again. But the reserve below it still carries the story on an interpretation panel, and the carvings themselves rest in Canterbury Museum, five hundred years of somebody's afternoon, still waiting to be picked up.