Richie McCaw and his team try ultimate test

Richie McCaw has his picture taken prior to beginning the Godzone Sdventure Sports Challenge in the Team Cure Fids in the Nelson. Photo / Supplied

Richie McCaw yesterday embarked on arguably his most brutal sporting challenge - lining up in the 530km GODZone endurance event that will see him and his Team Cure Kids teammates try to conquer New Zealand's great outdoors.

The four-strong team are wearing shirts emblazoned with No 7 - the number McCaw wore so famously for most of his 148-test All Black career.

The event started shortly before noon at Kaiteriteri and will see the 61 teams taking part in the gruelling challenge run, mountain bike and paddle on a route that traverses three national parks.

Teams are expected to complete the event in five-seven days.

Before setting off yesterday, McCaw spoke of the enormity of the challenge.

"I just hope I don't disgrace it. I'm looking forward to getting into it," he said.

"I guess it's a question of can you handle it. That's the bit that gets me going and until you do it, you don't know if you can.

"You open yourself up to failure, too."

He said the event would "push us all to the limits mentally and physically".

The team aim to raise $350,000 for the Cure Kids charity. They were just shy of the $300,000 mark yesterday.

Team leader Rob Nichol - the boss of the Rugby Players' Association - said they had been training hard and were now looking forward to the experiences the next few days will bring.

"Most of all I think we are just looking forward to getting under way - but also those special moments you get to experience in this race, be it nailing a challenge, some amazing scenery, exhilarating white water or some vertical cliff to abseil down, reaching that pass you have targeted for the best part of a day and a night, or getting a tough navigational call spot on," Nichol said.

"It's these moments which capture you for sure.

"As the Cure Kids team we have talked about wanting to work hard throughout the adventure for the cause, which is to raise funds to help find cures for kids."

McCaw's entry into the GODZone endurance event is his first major sporting event since retiring from rugby after leading the All Blacks to Rugby World Cup victory in the UK last year.

In August he is set to travel to Brazil to cheer on fiancee Gemma Flynn as her Black Sticks chase a medal at the Rio Olympics.

Richie McCaw of Team Cure Kids runs along the Kaiteriteri coastline during the GODZone multi day adventure race. Photo / Getty Images