For most people walking the length of New Zealand on the 3000km Te Araroa trail would be a tough challenge even in ideal conditions.
Sarah Matthews, however, is doing most of it by herself, in midwinter, and in memory of a close friend who died of cancer.
The Cambridge 29-year-old is in the final days of her six-month trek and fundraising mission for Bowel Cancer New Zealand.
She traversed the Far North's Puketi Forest, inland from Kerikeri, last weekend and will hit Raetea Forest, the last really gnarly section, any day now. She is likely to reach Cape Rēinga around July 7.
Most people walk Te Araroa from north to south and start in October-November so they do the bulk of the hike in summer.
Matthews, however, wasn't able to start until January 5, so for her it made sense to start at Bluff. Much of the South Island leg of the trail is impassable in winter due to snow and swollen rivers.
After working as an army chef for 12 years she was ready for a change and had planned to travel overseas.
When that was scuttled by the Covid pandemic she went looking for a challenge closer to home.
''I knew Te Araroa would be hard and I'd need motivation, so I thought if I did it for charity and in memory of my friend who passed away, then I'd have no choice but to finish it.''
Patrick Newton, who was also an army chef, died of bowel cancer in 2017 aged just 31.
He had symptoms for a long time but assumed they were caused by diet or lifestyle changes. He put his weight loss down to exercise.
''He was a typical Kiwi bloke, he shrugged it off and thought it'd be all right. There's a lot of fad diets out there and he thought the reason he was having irregular bowel movements and stomach pain was from eating dairy, so he tried cutting that out of his diet.''
When he was finally diagnosed, the cancer had spread throughout his body and he had just two weeks to live.
''They said he'd probably had it for five years. No 20-year-old thinks they've got bowel cancer.''
Matthews is encouraging people to donate to Bowel Cancer NZ — she has raised more than $1800 so far — and spreading the message that bowel cancer can affect people of any age.
''So if you have any health concerns get them checked out,'' she said.
Despite the long days and often rugged terrain, Matthews' biggest challenges have been mental rather than physical.
With few people on the trail due to closed borders and the time of year, loneliness is never far away.
''When I did the Tararuas (north of Wellington) I was alone for six days in a row. That was pretty lonely. Often there's no cellphone reception so you can't even text anyone. You're always thinking about the weight in your pack so you can't carry any books. Instead you end up lying in your tent at night thinking about how far you have to walk the next day,'' she said.
''I'd get to a town and see people and be so happy just to chat to people in a cafe.''
Loneliness, however, isn't a problem on her final section of the trail through Northland.
She was joined at Mangawhai by close friend Nicole Leger and they have teamed up with another solo walker, Elly Holland of Wellington.
The mental challenges of the trail were more than made up for by the people she met along the way, both trail walkers and ''trail angels'' (volunteers who offer accommodation, meals and encouragement).
She had been overwhelmed by kindness and generosity, and had loved being able to explore her own country.
''The South Island is just amazing. And I just love staying in those old backcountry huts and learning about the history of New Zealand,'' she said.
■ Go to linktr.ee/into_the_wild_nz to donate.