"The longer the search went on, the more concerned we were getting because she wasn't prepared, equipment wise, to stay a night out in the bush."
The Air Force helped the search today, sending a NH90 helicopter and its crew from Ohakea.
About 40 people, including Palmerston North and Whanganui police, DOC staff, Search and Rescue New Zealand, the air force and other volunteers had been involved in the search centered around the North Egmont Visitors Centre.
Weather at Mt Taranaki had been windy, with low cloud and temperatures down to about 5C.
A friend had been waiting for the woman at the car park.
When she was told today that her friend had been found safe and well, she told police it was "the best day of my life".
The rescued tramper is "tired and a little bit dehydrated but otherwise her spirits are high", Borrell said.
"She's walking around in a pretty good state of health considering she's spent three days in the bush."
The German visitor's parents have been informed of the good news by text, Borrell said.
Borrell said searchers were "jumping around pretty excited" when she was found.
"The whole aim of the search is to find missing parties safe and well."
Police will do a "full debrief" with her at a later stage, and find out how she survived.
"The biggest thing for us, is that if you go, for even a short walk within this national park, is that you tell someone of your intentions," Borrell said.
"This is what she didn't do on this occasion. If she'd gone up to the visitor centre and written in the intentions book where she was going to walk, it would've given us a better clue of where she was once she went missing."