Highlining is the latest adrenaline junkie trend. It has evolved from slack lining, a rapidly growing sport around the world. Unlike tightrope walking, slacklining relies on the rope being slightly loose, though still under tension, allowing for more bounce and the possibility for tricks. Highlining is the same except - you guessed it - much, much higher.

Last weekend's event was the brainchild of Hongkonger Andy Knight and the result of cross Asia-Pacific efforts, bringing together Chinese-born Australian Simon Li, and the rigging skills of New Zealander Shane Yates and Australian Matthew Perret. "Slackers" from around Hong Kong also joined in, eager to take their first tentative steps in the city's newest extreme sport.

But Zhang was the chosen brave for the maiden challenge, as he's one of China's top slackliners and 2012 winner of the Beijing arm of the world's biggest slackline competition.

Zhang admits he was a little apprehensive about the inaugural challenge, given it was more than double the height of any slackline he had attempted.

"Of course I was scared. Even the experienced highliners get scared sometimes," he says.

But once on the line, his nerves evaporated. "I was actually surprised out how confident I felt. I got up after only four tries."

The experience was vastly different for 26-year-old student Ricardo Iriarte. "It was indescribable," he says, still shaking from the nerves and the tension.

"You're so tired, you're scared out of your mind trying not tot fall off, the rope moves so much you're just using all of your energy to try and stop it from wobbling."

Unlike its tamer cousin, highlining offers a greater physical challenge, but Li, 27, agrees the mental ones are the greatest.

"Not having a fixed reference point of the ground below you throws off most people's balance. The fear of falling is always there, much greater than in rock climbing because the exposure is that much greater," he says. "Slacklining you can set it up between two trees in the park in five minutes; a highline can take hours to rig and the gear is expensive.

"As we put bolts in the rock, it took us a separate day to drill and bolt, then another day to rig the highline."

Established properly, there are few risks. "We have two of everything," says Yates, 29, a carpenter by trade who's rigged highlines all over the world.

"Two lines, in case the top one breaks, two rings, and two loops on the harness", he says. "It's pretty safe."

"The slacker is connected to the line and can't fall too far. If the line breaks, we have a secondary line set up which protects the slacker," says Knight.

"The only likely injuries are bruises and friction burns. Though it feels much more dangerous when actually walking the line."