A visit to the Waitomo Glowworm Caves is something of a rite of passage for young New Zealanders. The caves were first explored in 1887 by a local, Tane Tinorau, accompanied by an English surveyor, Fred Mace. They entered the caves via the Waitomo Stream, negotiating their way underground on a raft built from flax stems. First, they discovered the glowworms and then, using candles as light, they explored the lower levels of the cave. Later, on an independent trip, Tinorau discovered the upper level and an easier access. Authorities were advised, government surveyors mapped the cave, and it was officially opened to tourists in 1889.

I join a small group and enter the cave with Richmond, a local Maori guide with an extensive knowledge of the geology of the area. He tells us that Waitomo’s limestone was formed about 30 million years ago when the region was under the sea, and is composed from the bones and shells of billions of sea creatures. Over the last 24 million years, the limestone has buckled and been submerged, then separated into huge blocks. Rain then eroded the rock between the cracks and joints, creating the caves we see today.

It’s a cool 16 degrees Celsius inside as we wander through the upper levels, then take the stairs down to the 46-foot-high ‘cathedral’, where stalactites, stalagmites and other cave decorations adorn the cave floor, ceiling and walls. But the highlight for most comes at the end of the tour: an awe-inspiring boat ride through enormous caverns lit by the radiance from millions of glowworms.

Leaving the caves we head out to explore Waitomo’s scenic karst landscape, a mix of rolling, fertile farmland, with tall poplar trees marking cave skylights, and wonderful rocky outcrops stacked metres high, like carefully arranged chocolate chips.

The gravel route to the coast winds up to Haggas Lookout, from where the mountains of the Tongariro National Park can be seen on a clear day, and then continues on to Mangapohue Natural Bridge. Here, a ten-minute stroll leads to an impressive arch - all that remains of an ancient cave system.

Further on, another track meanders through the Piripiri Cave, although this one is best explored with a torch and solid footwear as the ground is slippery and steep. Nearby, at the Marokopa Falls Scenic Reserve, another easy ten-minute hike leads to the cascade, plunging 30 metres down a cliff face to the valley below.