What has 20 wheels and five pairs of eyes?
A convoy of professional skateboarders carving the shores of Bondi Beach.
Among them is Tony "The Birdman' Hawk", famous for his video games, even more famous for pioneering vertical skateboarding.
The 45-year-old American is in Sydney for the annual six-day skateboarding event Bowl-A-Rama, now in its 10th year.
Hawk retired from competition in 1999, before the concrete series was established in Australia.
"I'm excited to finally participate after seeing the action from afar for so many years," he said on Wednesday.
Also in Bondi with Hawk are members of the Bones Brigade - skateboarding legends Mike McGill, Steve Caballero, Lance Mountain and Nicky Guerrero.
The team are credited with helping skateboarding rise to prominence as a sport in the 1980s.
Event organisers say they're proud the event attracts professionals and up-and-coming riders.
"We started from such humble beginnings all those years ago and to be here 10 years later is truly amazing," said skate park designer Chad Ford.
