Caving is the recreational sport of finding and exploring caves. Speleology is the scientific study and exploration of caves.
Cavers would be the first to admit that they are an odd group. It takes a certain mindset to spend hours below the ground, often getting wet, dirty and cold, squeezing through narrow tunnels and abseiling down waterfalls. But cavers are underground explorers, and there are rewards, such as finding a deep passage where no one has ever been.
Caving as a sport
A group of cavers began exploring the lava caves in Auckland’s volcanic cones in the late 1940s. They soon progressed to limestone caves in the Waikato and at Waitomo in the King Country. Henry Lambert founded the New Zealand Speleological Society in 1949.
They faced many obstacles – few had cars, or even telephones to organise transport. Often exploring caves on farmland, they would sleep in shearing sheds or farmhouses. They used miners’ carbide lamps, and made rope ladders.
In 1955 the first headquarters were set up in an empty house near Waitomo. Many new caves and passages were found in the Waitomo area.
In 1957 a group of North Island cavers ventured south to Tākaka hill near Nelson, where a farmer led them to a hole he had never dared to enter. The cavers were ecstatic, estimating the maximum width to be 60 metres, and the depth 200 metres. They named it Harwoods Hole, after the original landowner.
On Christmas Day 1958, cavers were lowered into the abyss on a winch. David May, a schoolboy, was the first to go down, in a parachute harness with a steel seat. At a depth of 183 metres his feet touched bottom. Other members then explored 800 metres of passages.
A year later, the cavers returned, seeking a link to Starlight Cave, at the head of The Gorge Creek in the Tākaka Valley. They placed a green dye (fluorescein) in the stream at the bottom of Harwoods Hole, and it emerged four hours later in The Gorge Creek. Using explosives they blasted a stalactite block, allowing three cavers to make the first through trip. At 357 metres, Harwoods Hole (connected to Starlight Cave) was at the time the country’s deepest known cave.
Deepest and longest caves
Harwoods Hole is in New Zealand’s caving Mecca in north-west Nelson. Here, the marble within Mt Owen, Mt Arthur and Tākaka hill is riddled with subterranean passages. All but one of the country’s 30 deepest caves lie here.
The deepest cave is Nettlebed, on Mt Arthur. It was discovered in 1969, and in 1986 a connection was made with another cave, Blizzard Pot. Nettlebed has been mapped to a depth of 889 metres.
The longest cave is Bulmer Cavern on Mt Owen. Discovered in 1985, it has over 50 kilometres of explored length. Unusually, Bulmer is a dry cave, so explorers must carry water.
Some cavers aim to map a cave’s depth to 1,000 metres, and its length to 100 kilometres. The most likely place for this is in the Nelson marble country. Discoveries continue, and unmapped areas in existing caves await mapping. The major discovery since 2000s was Odyssey Cave on Mt Bell. In 2007 this had been explored to 296 metres deep and 1,700 metres long.
A helmet at Harwoods
Success turned to disaster at Harwoods Hole in 1960, two years after cavers claimed it as the country’s deepest known cave. Group leader Peter Lambert was being winched out of the hole when he was killed by falling rocks. It was New Zealand’s first caving fatality. Lambert’s helmet was placed on a cairn at the bottom of the cave as a memorial.
At some caves with drowned passages, enthusiasts use diving equipment. In the 1990s at Waitomo, Kieran McKay and others found underwater tunnels to dry caves, adding to the length of known passageways there.
Divers have also explored Nelson’s Riwaka Resurgence, the source of the Riwaka River. They do not always find pockets of air, but sometimes just submerged tunnels and shafts.
Cave diving can be hazardous. On 20 May 1995 Dave Weaver died while in a shaft in the Pearse Resurgence, at the base of Mt Arthur in Nelson. Two divers recovered his body in January 1997.