Karolin van Onna and her friend had dreamt about horse trekking the length of the South Island for years - and last summer they finally did it.

Karolin van Onna had been talking about horse trekking the length of the South Island for years and last summer she finally did it.

She and her friend Nicole Kumpfmueller spent three and a half months at the beginning of 2023 riding more than 1500km from Bluff to Picton on back-country trails.

Her horses, Moose, Rasta and Alex, were experienced and vet-checked thoroughly for the journey, van Onna told Country Life.

"We found it amazing how willing they were to keep going every day."

Hear about some of Karo's adventures horse trekking the South Island

https://players.brightcove.net/6093072280001/default_default/index.html?videoId=6348416102112

Originally from Germany, Van Onna has lived in New Zealand for more than eight years.

She runs a horse trekking business in Cromwell so the horses were used to journeys - but nothing as long as this.

At the beginning, the horses sometimes tried to turn around as if to say "time to go home now", she said.

"But after a while, I think they realised, 'Oh no, there's no turning back'."

While planning the journey, the women spoke to farmers and people who had done a lot of back-country horse riding - but learning to read the topographical maps was a baptism of fire.

A chance meeting with a local prevented them from getting stuck in a rugged mountain range - the elevation not immediately clear with their basic map-reading skills.

There were also quite a few big river crossings, which tested their skills.

"It was like pure adrenaline when you have to ride through a deep river and you're not quite sure how deep it's going to be and you're just trying to make it to the other side."

On the other hand, small creeks foxed her horse Moose.

"He just hated them and it would take so long every time to convince him to to get over.

"I would get off and try to pull him over and he just refused for like 10 minutes, and then suddenly he would jump on top of me!"

On top of map reading and planning where they would pitch their tent each day, up to 10 hours a day in the saddle was tiring, van Onna said.

They would hop off after about six hours and walk beside the horses.

"It does get exhausting ... not only physically, but mentally as well.

"It was always looking at maps and 'Where do we have to go next, and where does the track go and we're going to turn right soon' and you don't ever stop thinking about what's coming next."…

Go to this episode on rnz.co.nz for more details