You don't have to be mad to take on the annual Naki Run Amuck course - but it helps.
Hundreds of people dressed in their Sunday best took on the gruelling Urenui Beach challenge in the hunt for glory.
While many entered to claim a top spot, others like Brian Gardner were more interested in dressing up as his children's favourite Teenage Mutant Ninja Turtle.
Gardner said it was the second time he and his mates had ventured from Wellington to compete, and this year they decided to bring their families along. "It was really good. All the boys enjoyed it."
For Pip Mattock the race was about honouring a friend.
"A work colleague of ours, Wiremu Thompson, was in an accident and was killed on [State Highway 3] earlier this year.
"He was meant to be in our team. We are doing it for him."
About 770 people attacked either the 5km or 10km course, which included climbing ropes, swamps and an energy-sapping mud flat before a short Urenui River crossing.
Event director Evan Cottam said they had almost doubled the number of entrants from their first race two years ago.
"Everyone's a bit mad but they like the challenge and it's just a fun event," he said.
"When they finish they are absolutely stuffed but they enjoyed it, loving it."
Fastest male competitor over the 10km distance was Evan Lobb in 53 minutes 11 seconds and Carolyn Arthur claimed the top spot for the women with a one hour, nine minute run.
The New Plymouth North Rotary Club donated $13,500 to Taranaki Surf Lifesaving and a further $13,000 would go to the club's own charities.
- Taranaki Daily News
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