A BMX rider has performed tricks on a floating skatepark more than 2,000ft (610 metres) above the ground.
Kriss Kyle, 31, described it as a “once-in-a-lifetime opportunity”.
The British rider completed the world-first stunt, called Don’t Look Down, when he rode around a custom-made bowl suspended by a hot air balloon.
The balloon set off from Charlton Park Estate in Wiltshire and flew about 30 miles over the Cotswolds before touching down.
Kyle performed several highly technical BMX tricks in the short time window in February, and achieved the feat while wearing a parachute and contending with a constantly swinging bowl.
The Red Bull athlete, from Stranraer in Dumfries and Galloway, Scotland, has competed in professional BMX events since 2008.
He said: “I went straight to the edge, looked over and thought, ‘this is a once-in-a-lifetime opportunity’.
“All through riding that little bike, I was like, ‘this is one that I’ll be taking to the grave’.”
Kyle said the idea of a floating skatepark came to him whilst out mountain biking with his dogs in lockdown, before he pitched the idea to his manager at Red Bull.
He added: “This was pretty much the same as I go into every project – if you want it bad enough, just keep visualising it and sure enough you can turn that into a reality.
“No one’s ever really done anything like this, and it’s a big bit of kit. It’s actually registered as an aircraft, which is insane.”
Very specific climatic conditions, including wind speeds of less than three miles per hour, were required to make the flight possible.
Engineers at Red Bull Racing needed to make the bowl with less conventional materials, in order to make it lighter and buoyant enough to float at 1.6 tonnes.
Rob Gray, technical director of Red Bull Advanced Technologies, said: “The original wooden bowl was a sort of prototype – they built that bowl to check Kriss could ride it and to define the shape that they wanted.
“The whole focus for us really was on getting the weight down. To do that we used carbon fibre, which is the same material we make the Formula One cars out of.”
Having been involved in previous high-profile projects including Kaleidoscope and Out of Season, Kyle said his latest project was “definitely up there” as one of his best, adding: “It’s been an incredible experience from start to finish.”
He said that filming for his next stunt, which will take place in Switzerland, was due to begin in October.