It's been a long time since the famous Pink and White terraces were last seen.
But thanks to science and technology, visitors to Waimangu Volcanic Valley can now "witness" what was once known as the Eighth Wonder of the World.
A new augmented reality (AR) app has been launched today that allows visitors to use their phone/device when prompted as they explore the valley.
Through a process of computer-generated graphics and software, the app will bring back to life historical sites of significance.
Waimangu Volcanic Valley general manager David Blackmore said developers had used a variety of resources to develop the app, including work from early explorers Ferdinand von Hochstetter and Charles Spencer, work by GNS and research by Niwa.
"Old reference photos and paintings have also been used to recreate the terraces in AR," Blackmore said.
"AR is not new, but the technology we have available to us through our devices is and this is what has made the recreation of the terraces possible. Having the old images brought to life by the latest in technology is really something to see."
In conjunction with the launch of the app, Niwa has today published new research that reconstructs the terraces.
The research by Niwa scientist Dr Andrew Lorrey and John-Mark Woolley appears in the scientific journal Frontiers in Earth Science.
Waimangu Volcanic Valley chairman Alan Skipwith (Tūhourangi) said, for many New Zealanders, the Pink and White Terraces formed part of the classroom curriculum.
"For international visitors, they're intriguing because so many European travellers gathered to experience the natural spa and health benefits the terraces provided, as well as the mystery about where they are now.
"This is the closest we can get to restoring the natural taonga of Te Tarata and Otukapuarangi.
The app has been built by Rotorua company Digital Elements along with Specialist Apps in Australia.
One of the creators, Leon Thomas, said AR did not replace real life in the way VR headsets did, instead it added a layer of interest and excitement over what was already visible.
"Locations of interest are geo-tagged, so once you've got the app, your device will let you know when there is something you can see through AR."
Although the Pink and White Terraces will be a key attraction, the app also reveals fascinating geological insights like the now-extinct Waimangu Geyser, which regularly played in the valley between 1900 and 1904.
The app has been in development since February and is free to download on Apple and Android devices.