Long ago Waitomo Caves staff named two eels living in the cave system "Smeagol" and "Gollum".
These names, from a Lord of the Rings character famously played by Andy Serkis, seem prophetic.
Last month marked 125 years since guides first showed tourists through the caves.
Now the Waitomo Caves Systemoperators, Ruapuha Uekaha Hapu Trust and Tourism Holdings Ltd (THL), have hobbits in mind.
Waitomo Glowworm Caves is working with Hobbiton Movie Set Tours and Te Puia to run Middle-earth Trilogy tours, aimed at the youth and backpacker markets.
These will include a Black Labyrinth Tour (The Legendary Black Water Rafting Co) at Waitomo, a guided tour at Matamata's Hobbiton Movie Set and the Steambox experience at Te Puia in Rotorua.
Serkis did an Abyss tour at Waitomo to get in character ahead of the first movie in the series, The Fellowship of the Ring. Sir Peter Jackson and Fran Walsh did a Labyrinth tour with their daughter.
And later audio, to run alongside underground scenes in Hobbit movies, such as Gollum's pool and Smaug's Hall, was recorded in Ruakuri and Cathedral Caves.
THL chief executive Grant Webster says the caves are one of New Zealand's oldest tourist attractions, "and so it's exciting to think they'll also soon be linked with the country's best known movies".
"In 1889 local Maori opened the doors to visitor tours and it's been a very special place for locals and visitors ever since," Webster said.
"Generations of Kiwis have gazed in wonder at the sights they've seen in these cave systems."
