The layered, Brutalist concrete of the National Theatre might've been designed as a Free Running paradise, were the sport in vogue in the 1970s.
Happily, tonight, Red Bull Art of Motion will use the theatre's distinctive architecture as a temporary Free Running course. Twenty five of the world's best free runners will leap and flip their way across the multi-levelled building, hoping to impress a panel of four judges.
The top 12 contestants will then advance to the finals, where they'll be judged on their "creativity, execution and flow."
Hotly tipped to do well are 3 of the world's best free runners, Ryan Doyle from Liverpool, Tim Shieff from Derbyshire and Blue, aka Paul Joseph.
Get there early to get a good spot.