Think of a cross between walking a tightrope and bouncing on a trampoline, and you’ve got the gist of slacklining. It is a balancing act on thin, stretchy tape, usually not very far from the ground. Beginners wobble slowly along the webbing and fall off. Experts leap from line to line, performing somersaults, chest bounces and other astonishing tricks. There are variations: highlining (crossing terrifyingly high chasms); timelining (staying on for hours) waterlining (over water); even yogalining. It is good for balance, of course, but also for focus, agility and core strength.
Urban slacklining can be done anywhere; between two trees in the park, say, or two lamp-posts in the street. The map at ukslackline.com shows up to 40 clubs and groups. At the Project Climbing Centre in Poole there are twice-weekly slacklining sessions for all abilities at just £1 a pop. The sport has also started to appear at festivals, such as the Bristol Harbour Festival (18-19 July). In fact, there are now entire events devoted to slacklining, such as the inaugural Northwest Slackfest, which took place in Cheshire in May. Roll on next year. Rachel Dixon