Search crews continue to scour Mt Aspiring National Park for a missing British tramper Stephanie Simpson while her family and friends wait for news.
Stephanie Simpson left to go tramping over the weekend around Mt Brewster.
But the alarm was raised yesterday morning, sparking land and air searches.
Her boss, Douglas Peddle, was expecting her to walk through the door of his Wanaka business Doug the Gardener on Monday morning.
But when the 32-year-old woman from Essex didn't turn up and her friends didn't know where she was, he contacted the police.
Simpson was keen to explore New Zealand while on a working holiday, and had the experience and equipment, Peddle said.
"She's very fit and healthy, came over from the UK and was keen to explore everything this region has to offer. She'd been doing some tramps in the area and went away last weekend."
He has been in contact with her family and said they were concerned but were trying to stay positive.
A helicopter scoured the area yesterday, but to no avail.
Earlier this morning, the search resumed with a search dog and handler, the Fox Glacier Alpine cliff rescue team and Wanaka LandSar volunteers involved in finding Ms Simpson.
Phoebe Crawford hiked up to Brewster Hut on Saturday, a more than 1000 metre climb, and said it was a beautiful day with lots of sun, and no wind or rain.
"The track was a little bit muddy on the way up. There was water on the track," Crawford said.
"However you have to cross the river immediately when you walk to Brewster Hut and that was a really low flow. The river probably came up to my shins."
While she didn't see Simpson, Crawford said there was a lot of people about over the weekend.
"It's a gruelling climb through the bushline. It took us an hour and a half to get up through the bushline, and there's a lot of tree roots.
"You really have to think about where you put your feet and occasionally you have to use your hands to pull yourself.
"A decent fitness level would be handy, but also I guess you just have to be comfortable on your feet in those sort of conditions."
The search area includes Fantail Falls to Mt Brewster, the Brewster Hut, Mt Armstrong track and Makarora Valley.
Mountain Safety Council chief executive Mike Daisley said the main track up to Brewster hut was more of a test of fitness than navigation, but conditions get tricker once you ventured beyond the hut.
That could make the search for Simpson a challenge, he said.
"An individual could have chosen any number of little side tracks. If you follow (one) out to the Brewster glacier, there's a lot of steep bluffs and it's a very rocky area so there's a lot of area to search, particularly if people have slipped... there's a lot of loose rocks and difficult to navigate in."
Her friends describe her as bright, bubbly and an experience tramper.
A family friend, who didn't want to be named, said they're all focusing on the search and police enquiry, and didn't want to speak at this stage.
The police were appealing for anyone who may have spoken to or seen Ms Simpson to contact them.
Two people were found dead in the national park over the weekend, but police said they were not believed to be connected to the missing person search.
The search is expected to resume tomorrow, with thermal imaging.