The Waitomo Caves are a village and cave system forming a major tourist attraction in the northern King Country region of the North Island of New Zealand, 12 kilometres northwest of Te Kuiti. The community of Waitomo Caves itself is very small, though the village has many temporary service workers living there as well. The word Waitomo comes from the Māori language waimeaning water and tomo meaning a doline or sinkhole; it can thus be translated to be water passing through a hole. These Caves are believed to be over two million years old.
The most renowned animal in the cave is the glowworm Arachnocampa luminosa. There are several small underwater lakes that were created by freshwater creeks or brooks.
The walls of the caves are covered with a variety of fungi including the cave flower (a distant relation to the genus Pleurotus) that is actually a mushroom-like fungus. The most common animals in the caves are insects. This includesalbino cave ants, giant crickets, and of course the glowworms.
Geological and volcanic activity has created around 300 known limestone caves in the Waitomo region over the last 30 million years.
The limestone formations in the Waitomo Glowworm Caves were formed when the region was still under the ocean about 30 million years ago.The limestone is composed of fossilized corals, sea shells, fish skeletons, and many small marine organisms on the sea beds. Over millions of years, these fossilized rocks have been layered upon each other and compressed to create limestone and within the Waitomo region the limestone can be over 200 m thick.
The caves began to form when earth movement caused the hard limestone to bend and buckle under the ocean and rise above the sea floor. As the rock was exposed to air, it separated and created cracks and weaknesses that allowed for water to flow through them dissolving the limestone and over millions of years large caves were formed.
The stalactites, stalagmites, and other cave formations grew from water dripping from the ceiling or flowing over the walls and leaving behind limestone deposits. The stalagmites form upward from the floor while the stalactites form from the ceiling. When these formations connect they are called pillars or columns and if they twist around each other they are called helicti. These cave decorations take millions of years to form given that the average stalactite grows one cubic centimetre every 100 years.
Today, a number of companies, large and small, specialise in leading tourists through the caves of the area, from easily accessible areas with hundreds of tourists per hour in the peak season, to extreme sports-like crawls into cave systems which are only seen by a few tourists each day. A visit to Waitomo Caves made Number 14 amongst a list of 101 “Kiwi must-do’s” in a New Zealand Automobile Association poll of over 20,000 motorists published 2007, and in 2004, around 400,000 visitors entered caves in the area.