Antek Marciniec holds onto a slackline after falling off as he highlines between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. Slacklining is a balance sport in which participants walk on a flat nylon webbing anchored between two points with the tension adjusted to allow for slack, providing an experience similiar to that of walking on a trapmoline. Highlining is a style of slacklining where the two anchor points are set up with significant elevation from the ground or water. (Photo by Cameron Spencer/Getty Images)

A slackline is rigged between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Matt Macelli focuses on a slackline before highlining between two cliffs on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Matt Macelli walks along a slackline as he highlines between two cliffs on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Slackliner Kyle Beall focuses on a highline between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Luke Sarantos walks on a slackline as he highlines between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Matt Macelli focuses on a slackline as he highlines between two cliffs on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

A secondary rope and a highline are rigged between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Antek Marciniec walks along a slackline as he highlines between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Luke Sarantos walks on a slackline as he highlines between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Slackliners adjust the tension of the webbing on their slackline rigged between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Kyle Beall walks on a slackline between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Kyle Beall focuses on a slackline as he highlines between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Matt Macelli walks along a slackline as he highlines between two cliffs on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Luke Sarantos checks his harness and makes final preparations to a slackline between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Kyle Beall walks on a slackline between two cliffs at Diamond Bay on December 21, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)