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Dunedin's secret pools

While most baths have plugs, not all of them can claim to be made from them.

At the end of Dunedin's Blackhead Beach you'll find a series of improbable pools made out of artificial-looking basalt plugs. It's hard to believe that the interlocking columns which make the "Roman Baths" are entirely natural.

The unusual rocks are similar in makeup to Dunedin's celebrated Organ Pipes formation, but these columns' dramatic seascape setting makes them even more remarkable. Cold South Sea waters create a scene reminiscent of the Giant's Causeway in Northern Ireland.

Beware though, the stunning location makes the area treacherous and should be visited only in clear conditions.

Nelson's stately Mud Castle

The crenulations of the stately building look as if they belong in the South of France, not Nelson. However, The Mud Castle is the – slightly eccentric – vision of owners Kevin and Glenys, who bought a small section of scrubland in 1990.

The self-styled lord and lady of the castle set about convincing an army of Wwoofers and backpackers to build their vision out of adobe mud bricks – mostly by hand.

30 years later, the result of this lofty dream is a unique BnB and events venue. It was built out of local materials and largely powered by solar energy. For a grand design made using prehistoric construction and labour techniques more befitting Egyptian pharaohs, the Mud Castle is extremely forward-looking.

The world's largest natural concert hall

Jacques Cousteau, the enigmatic French grandfather of scuba diving, famously named Poor Knight's Island one of the best dive sites in the world. While the praises of these rich underwater treasures are regularly sung, one of the island's most impressive assets is found above the waterline. The Rikoriko Cave is a sight to behold and a marvel for the ears.

Musicians from around the world, including choirs, yodellers and Auckland's own Neil Finn have praised the cave's acoustics.

Even if you're not lucky enough to catch an impromptu performance, it is a memorable trip from Tutukaka. At 221,494 cubic metres, it is the largest sea cave in the world.

The West Coast's constantly shifting ice maze

Franz Josef Glacier is one of New Zealand's most recognisable landmarks. But it's rarely seen from this angle. Tourists have been guided through the ice tunnels criss-crossing the ice flow since the early 1930s, however, it is never the same twice.

The crystalline labyrinth of caves is constantly changing. Sometimes moving as much as 50cm a day. Despite periods of growth, the slow-moving ice river has been retreating up the valley since it was first visited by humans.

Auckland's not so forbidden city

In South Auckland's Flat Bush, you will find a temple complex that would not look out of place in medieval China. The Fo Guang Shan temple is a 1.6ha Buddhist temple and gardens built in the style of the Tang Dynasty.

The palatial building dedicated to the Chinese branch of humanistic Buddhism features an oriental courtyard and two-tonne prayer bell. As the largest building of its kind in the country, it is the spiritual centre of Humanistic Buddhism in New Zealand.

Open to non-Buddhists, it runs a programme of Chinese cultural events and a vegetarian restaurant and tea house.

Stonehenge Aotearoa

In the Wiltshire plains of southern England stands the 10,000-year-old mystery of Stonehenge. In rural Wairarapa, the Stonehenge Aotearoa is a lot more recent, but no less mysterious.

A modern interpretation of what archaeologists believe the Salisbury henge might have looked like, the attraction in Ahiaruhe is a practical experiment in living archaeology and astrology. Combining modern science with ancient "star lore", the henge is informed by ancient traditions shared by Celtic, Māori and even Egyptian cultures.

Visitors today are treated to a tour of the cosmos and ancient history. With Star Safaris every Friday and Saturday (weather permitting) you can combine some prehistoric astrology with modern-day stargazing through high-powered telescopes.

Waikato's Forest Church

In a quiet, leafy corner of the Waikato is a church that appears to have sprouted from the ground. The Tree Church in Ōhaupō is made from living plants. Using cut leaf alder to form the roof, and New Zealand purple hop bush (ake ake) to form the walls, arborist Barry Cox designed the chapel as a place for worship and contemplation.

However, at the centre of a private garden, the chapel is rarely open to visitors.

Only opening to the general public on Sundays and weddings, the current owners ask anyone wishing to visit the chapel to get in touch via their website.