Beneath the Waikato Museum, beyond where the public are normally allowed to go are the lower levels where more than 30,000 items are stored when they're not on public display.
The museum's Collections Manager, Stephen Pennruscoe says the main collection storage room is at the core of the building.
"We're right in the heart of the building and I guess this is the metaphorical heart of where the collection sits, this is the main collection store."
30 years ago on October 3rd is the exact date of Te Whare Taonga O Waikato opened its doors to the public. Since that day in 1987, it's become one of New Zealand's most significant museums and art galleries - and home to more than 30,000 artefacts.
"There's no mechanical temperature control, it's all done through the thermal mass of the building, so the difference in temperature from winter to summer is only a few degrees," Mr Pennruscoe says.
Massive paintings are stored on giant sliding racks and the museum is the kaitiaki of several private collections including that of former Ohaupo farmer, Barry Hopkins,
"Works on paper can only be displayed for short periods of time due to exposure to ultraviolet light, so it's better that they are kept down here and brought out when appropriate" Mr Pennruscoe says.
And smaller artworks on paper and care are kept in special cases known as a solander box.
"The solander box is an archival, acid-free box, obviously it locks out all light. So it's a perfect storage vessel for holding works on paper. These works are all matted so it means that the artwork is protected within the matting frame as well."
To mark the 30th anniversary of the building, Waikato Museum has two new exhibitions; Te Haerenga The Journey: Toward Te Whare Taonga o Waikato, and Ngaa Taonga: Treasures from Waikato Museum.
Curator, Dr Dan Morrow says the exhibitions are always changing and there's always a new variety of stored objects on display. To choose items for the celebratory exhibitions, he says "we talked about a selection of items from the Museum's vaults and we were looking for items that didn't necessarily represent the absolute best things in the museum's collection, but rather things that had engaged us in recent years," Mr Morrow says. "So it's very much a personal selection and something of a whimsical selection as well I guess."
But out of the 30,000 items, Dr Morrow says one of his favourites is a miniature classic train - Ivanhoe.
"The museum acquired it in the early 1970's and the model was produced by a man named Victor Hurley who was a local Hamiltonian. He worked for the NZ Railways out at Te Rapa and at Frankton and he fabricated the model himself over a period of years - painstakingly using materials that he acquired himself. So the train really was a labour of love," Dr Morrow says.
That train and other taonga feature in a new book that recounts the museum's history.
Anniversary celebrations at Te Whare Taonga O Waikato last until the end of November.