Competitors in the Alexandra Carousel Backyard Ultra, to be held at Alexandra Airport, will complete a 6.7km loop every hour, on the hour, until there is only one person left.
Event co-organiser Tom Heath said he had the idea for the event 18 months ago.
Having run a few backyard ultras, he really loved the format.
The social aspect of the races set them apart from other race events such as marathons, he said.
"You can be talking to one person one lap, and then the next lap you’re talking to someone else."
That was in contrast to a half- or ultra-marathon where as soon as the starting gun was fired, the leading pack went off and was never seen again by other racers, he said.
Co-organiser Hannah Presswood said another aspect of backyard ultras was that it was about who could endure the longest as opposed to who was the fastest.
"With a backyard ultra, the point is to go until you can’t go any more."
People might turn up and hope to do eight laps and then end up doing 13, or better than they had ever run before, she said.
Part of the race entry fee would be donated to charities Bowel Cancer New Zealand and I Am Hope.
The choice of charities was important to Mr Heath.
Bowel cancer was something that had affected him personally, with family members dying from the disease.
The connection between mental resilience and endurance racing was why I Am Hope was chosen, he said.
"It’s just something that I think they go hand in hand, backyard ultras and mental resilience."
So far, the organisational process was looking good, Mr Heath said.
"So with the airport, that’s council land, so we have a kind of pre-approval for that ... We’ve got to finalise that approval, but things do look pretty good for it."
Mountain Bikers of Alexandra and people who lived near the airport had also been supportive, he said.
Ms Presswood said the response from businesses had also been great so far, with prizes and sponsored entries being provided by four companies.
She was "grateful and really stoked with that. And we do expect a few more to roll in as well".
They hoped the Carousel would become annual event.
The race starts at 9am on Saturday, April 19, and would continue until there was only one competitor standing.
— Ella Jenkins
