A couple rescued from Mount Holdsworth in Wairarapa on Saturday night would have likely suffered from hypothermia had they not been found in the dark, police say.
The couple had planned a gentle walk from Holdsworth Rd to Atiwhakatu Hut and on to Jumbo Hut for the night.
However, they took a wrong turn that led them up the East Holdsworth Track and close to the ridgeline.
After the couple realised their mistake, they attempted to reroute to Powell Hut, but faced extreme weather conditions and were "blown off their feet several times".
At around 4.15pm the pair hunkered down and called police. They were fortunate to have a cell phone and be within cell phone coverage for the call to get out.
They had huddled together for several hours in the cold in the worsening weather conditions.
The couple were finally rescued from the mountain's ridgeline seven hours after the initial alarm was raised.
Wairarapa acting sergeant Richard Butler said a team of three LandSAR members successfully located the pair at around 11pm, and managed to get them to Powell Hut where they spent the night before safely escorting them down to the road on Sunday morning.
"A helicopter was considered, but high winds meant it could not be deployed.
"The pair were fortunate to have had cellphone coverage, but people should never rely on cellphones solely as their means of communication.
"A quality Personal Locator Beacon (PLB) can be purchased for under $500 which will last up to 10 years, that's $50 a year to potentially save your life, alternatively, you can hire them from various trusts for the price of a box of beer.
"A distress beacon lets you instantly signal for help and they work almost anywhere in the world.
"The beacon shows rescuers your approximate location, taking the 'search' out of search and rescue.
"The sooner rescuers can help you, the more likely you are to survive."
Butler encouraged trampers to always be prepared and take sufficient clothing and equipment for an unplanned overnight stay.
"The Rescue Coordination Centre New Zealand works 24/7, 365 days of the year responding to all distress beacon activations.
"The team acts quickly to find out as many details as they can about who set off the distress beacon and promptly send search and rescue teams to assist when an alert comes in.
"People heading into the mountains should seek information from the Department of Conversation (DOC) visitor centres or via the DOC website.
"It can give you detailed information about weather forecasts, track issues and conditions."