The invitation-only event saw 20 surfers such as Australian legend Mick Fanning and 2016 defending champion Russell Bierke tackle the famous 'Shippies' when a wave within a wave is created due to the shape of the reef bottom, causing several steps to emerge.

One of the most difficult surf locations in the world, Shipstern Bluff was first surfed in the early 2000s with triple-overhead waves up to 20ft [6m] commonplace.

Contestants used impact jackets to help absorb shock from serious wipeouts in 12-degree water temperatures with frigid southerly winds also posing problems.

Surfing's unique big-wave event saw Florence, 24, start Monday strong in heat one after opting to paddle for the entire event instead of using the tow rope.

Three-time world champion Fanning got towed in, however struggled to master the giant waves in the heats like Hawaiian Florence and Tasmanian chargers James Hollmer-Cross and Mikey Brennan.

In the final, which Bierke just missed out on a spot in, Hollmer-Cross, the only one to tow, stole the show when he scored a perfect 10 that hollowed out, swallowed him up then spat him to the channel.

Florence paddled into and successfully negotiated a double-overhead barrel and Shipstern's notorious 'step' to score an excellent 9.33 to cement himself as the one to beat and followed up with a 5.83 to seal the win as Hollmer-Cross failed to find a second wave.

Australian heavyweight Laurie Towner grabbed second place with a combined 14.10 as compatriot Justen 'Jughead' Allport secured the final podium spot.

"I'm so baffled, it's the first contest I've ever won Florence, whose older brother John John (two-time WSL men's world champion), said.

"To be at this venue and win is amazing.

"To be surfing with the boys and the local legends, I just can't believe it - I'm so psyched.

"We drew straws to decide priority and, as soon as the horn blew, I was looking at this thing going, 'It's mine!'

"It was the best wave I caught.

"James had that unbelievable wave - it was perfect and he got a perfect score, but I'm so stoked he couldn't get another one... I was counting the minutes.

"It was the longest hour of my life."

This is only the third time Red Bull Cape Fear has run in six years, after Sydney's ledge-break "Ours" editions in 2014 and 2016, as contestants and organisers have to wait for serious and dangerous conditions that provide the ultimate test for the best global surfers.