The Waitomo Glowworm Caves attraction is a cave at Waitomo on the North Island of New Zealand, known for its population of glowworms, Arachnocampa luminosa. This species is found exclusively in New Zealand.
The Māori had known about the caves for quite some time before the local Māori Chief Tane Tinorau and an English surveyor, Fred Mace, did an extensive exploration in 1887. As they began their journey, they came across the Glowworm Grotto and were amazed by the twinkling glow coming from the ceiling. As they traveled further into the cave their first discovery was the Glowworm Grotto with its myriad of tiny bright lights dotting the cave ceiling. As their eyes adjusted to the darkness, they saw a multitude of lights reflecting off the water.
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.