Caving Areas in the Nelson Region

From Takaka Hill, south to the Arthur range and to Mt Owen, there are thick beds of marble.

Mt Owen covers a large geographical area which includes Mt Bell, Replica Hill, Sentinel Hill and Cullifords Hill. Access to the area is via the Owen River or Granity Pass, both of which are energetic walks in especially if carrying a heavy pack. Mt Owen still has many unexplored areas which offer the potential for new discovery and exploration. Expeditions into the region usually employ the use of helicopters to transport equipment, supplies and cavers into to the desired area (heli-caving).

Mt Arthur covers a smaller geographical area than Mt Owen and is more accessible. The two main systems on Mt Arthur are The Ellis Basin System and Nettlebed Cave. The latter being the deepest cave in New Zealand at 890m and with 25 km of explored passage. The Ellis Basin System is 775m deep and has nearly 29 km of explored passage.
Twin Traverse Tomo which lies high above the Ellis Basin has been pushed to a depth of 400m and if connected to the Ellis Basin System would give a new depth record of over 1300 m.