The Waitomo Glowworm Caves attraction is a cave at Waitomo on the North Island of New Zealand. It is known for its population of "Arachnocampa luminosa", a glowworm species found exclusively in New Zealand. This cave is part of the Waitomo Caves system that includes the Ruakuri Cave and the Aranui Cave.

The limestone formation in the Waitomo Glowworm Caves occurred when the region was still under the ocean about 30 million years ago. The limestone is composed of fossilized corals, seashells, 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.

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