Two "ill-prepared" men who climbed to the summit of Mt Ngāuruhoe dressed in jeans and cotton sweatshirts were rescued by police at the weekend.
About 4pm on Saturday a climbing party reached the summit of Mt Ngāuruhoe in winter alpine conditions and were "amazed" to discover the cold and frightened pair.
The men dressed in street shoes, jeans, cotton t-shirts and cotton hooded sweatshirts unsure how to descend the mountain, and had no alpine equipment, in rapidly increasing icy conditions, police said.
The climbing party fed the men, provided warm clothing and, after some dialogue via Google translate, called 111 to ask for police help.
Police sent Midwest Helicopters to the summit to fly the pair off the mountain.
"This would be one of the worst examples I have seen in recent years of day-walkers with inadequate knowledge, equipment and skill, climbing in an alpine environment, Constable Mark Bolton from National Park Police said.
"They are incredibly fortunate that the well-prepared mountaineers were able to render assistance and put the call out for help because I doubt they would have survived the night otherwise."
At least two other climbers had attempted to turn the two men around during their ascent of the mountain, concerned with their lack of clothing and equipment.
Senior Constable Conrad Smith told Checkpoint in his 17 years of search and rescue in the central North Island, this would be "in the top couple of jobs that I've dealt with in terms of being ill prepared".
They needed to have - and know how to use - alpine kit like ice axes, helmets, shovels, cramp-ons, and avalanche transceivers, Smith said.
The people who stumbled across the pair tried to communicate with them and come up with the best plan.
"They actually ended up discouraging them from trying to make their way down because it was just too dangerous so they contacted police and we got a rescue plan underway."
It was a sunny day but "as soon as that sun dropped down in the evening and the temperature plummets really quickly into the negatives".
"They definitely weren't dressed to spend the night up there, it would have been very, very cold and I doubt they would have survived that and I also don't think there was any way they were going to be able to get down the mountain with the conditions icing up and getting slippery - if they had have tried they would have come to grief with a big fall, a big slip."
Smith said it was frustrating as the Department of Conservation did a lot of work to push safety messages, in person, online and on the track.
The track had the most search and rescues in New Zealand, he said.
"In the winter it's an alpine mountain and there's snow and ice up there, people have got to remember that."
Police urged people heading into the outdoors to be adequately prepared. They encouraged anyone heading into the back country to check in with the local Department of Conservation visitor centres for up-to-date advice on weather, conditions, equipment and local knowledge of any intended routes.