Harwoods Hole is a cave system located in the northwest of the South Island of New Zealand, in the Abel Tasman National Park. At , it is New Zealand's deepest vertical shaft. It was first explored in 1958, long after it was discovered.

Formation

Evidence suggests that run-off from an area of approximately 20 square km converged into a stream that then flowed down a dry valley to create what is now Harwoods Hole. Since then the river appears to have changed course. Subsequently, Harwoods Hole receives water through

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...

s and surrounding dry valleys; this water then percolates through surrounding rock ensuring it becomes saturated with calcite, before entering the cave where the calcite is deposited. This second phase means that rather than expanding, Harwoods Hole is being filled in.

History

It is one of several important

cave A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...

systems in Tākaka Hill, between

Golden Bay Golden Bay may refer to: * Golden Bay / Mohua, a bay at the northern end of New Zealand's South Island * Golden Bay (Malta), a bay and beach on the coastline of Malta * Golden Bay High School Golden Bay High School is a secondary school A s ...

and

Tasman Bay / Te Tai-o-Aorere Tasman Bay (; officially Tasman Bay / Te Tai-o-Aorere), originally known in English as Blind Bay, is a large V-shaped bay at the north end of New Zealand's South Island. Located in the centre of the island's northern coast, it stretches along ...

. Starting at the surface as a diameter entrance and descending , Harwoods Hole is New Zealand's deepest vertical shaft. Further in it connects with Starlight Cave. The long rope descent is considered one of the most spectacular parts of the

caving Caving – also known as spelunking in the United States and Canada and potholing in the United Kingdom and Ireland – is the recreational pastime of exploring wild cave systems (as distinguished from show caves). In contrast, speleology i ...

experience at Harwoods. Harwoods Hole has an overall depth, defined as height above sea level of entry to height of outlet, of . Henry Harwood (1844–1927), with John Horton and Thomas Manson, opened up the Canaan Downs area and discovered Harwoods Hole, though it was not immediately entered. It remained untouched until seven cavers explored it over the 1958/59 summer. With a home-built

winch A winch is a mechanical device that is used to pull in (wind up) or let out (wind out) or otherwise adjust the tension of a rope or wire rope (also called "cable" or "wire cable"). In its simplest form, it consists of a spool (or drum) attach ...

weighing , the first person was lowered down on 28 December 1958. Upon completion of the initial exploration, Harwoods Hole became the deepest explored cave in New Zealand, a record that was later broken by Nettlebed Cave in the nearby Mount Arthur region. The following summer, 21 cavers explored Harwoods Hole further. The team was also interested in finding the outflow of the underground stream. They suspected that The Gorge Creek at East Tākaka was the outlet as the flow rate matched, and green dye released inside Harwoods Hole was soon visible when it emerged at Starlight Cave, so named by the cavers where The Gorge Creek emerged. With the connection confirmed, a squeeze was widened by gelignite and a connection from Harwoods Hole to East Tākaka for cavers was thus established. On 4 January 1960, Harwoods Hole was the site of the first fatality by a member of the New Zealand Speleological Society when the leader of the caving expedition, Peter Lambert, was killed by rock fall. A cairn at the bottom of the shaft with Lambert's helmet placed on it acts as a memorial.

Access

Near the top of Tākaka Hill on State Highway 60, an unsealed side road leading to Harwoods Hole is sign-posted. After , a car park is reached. From here, a walking track gives access to Harwoods Hole. The hole is not fenced.

References

External links

Harwoods Hole Caving GuidelinesNew Zealand Speleological Society Homepage
{{Tasman District Caves of the Tasman District Sinkholes of Oceania