Katherine resident Jess Di Pasquale and Darwin-based Natalie Bell are taking on the race, billed as the toughest in the world, to raise money for two charities: Sock it to Sarcoma and Steppe and Hoof.

Ms Di Pasquale said the pair were close friends, and their friendship stemmed from a shared love of horses and participation in pony club events.

"We've known each other for quite a while," she said.

"She was always in Darwin and me in Katherine. We were on different teams to start with, but then we started competing nationally together and the friendship just grew from there."

The Mongol Derby recreates the world's first postal route, a horse messenger system devised by Genghis Khan in the 13^th Century.

The Katherine resident said she and her riding partner signed up because they wanted to experience new challenges.

"For me it was just a bit of a personal challenge, it's the same for Nat too," Ms Di Pasquale said.

"I'd had a couple of kids, and just felt like I needed a new challenge."

Competitors in the derby raise funds for the charity Steppe and Hoof, which supports Mongolian herders and Jess and Nat are also raising money for cancer charity Sock it to Sarcoma.

Ms Di Pasquale said the desire to get the most out of life was not the only reason they were competing in the race, and they chose the charity honour of their late friend.

"One of our friends who used to ride with us at pony club died from one of the rarest forms of sarcoma in 2017," she said.

"She was an adventurous type, a happy-go-lucky sort of person. If she was still here it's definitely something she would be keen on doing as well.

"In her honour, we'll be raising money for the charity she had a lot to do with before she passed."

The derby is a challenging race, with competitors contending with the terrain, weather and semi-wild Mongolian horses. Approximately half of the competitors drop out of the race before the finish line.

Neither rider has experience riding such a large distance in such a short amount of time, although Ms Di Pasquale has worked on cattle stations and is no stranger to a long day in the saddle.

Despite this, the rider said the two women had been undertaking endurance rides when they could and was confident they'd both cross the finish line.

"There's a fair bit of luck involved in it," Ms Di Pasquale said.

"There's a lot of factors that knock people out.

"We're pretty positive. Something like this you've got to try and go in as positive as you can. If you're mentally ready for it, then you're probably reasonably right."

The team will host a fundraising night for Sock it to Sarcoma at the Katherine Country Club on June 25, with trivia, raffles and more. A link to tickets can be found on the team's Facebook page.