In pictures: Bouncing beneath Blaenau Leigh Amor

BBC Wales Online Published duration 24 June 2014

It's already home to the world's longest zip-wire, now Gwynedd boasts what is believed to be the world's largest underground trampoline in the abandoned Llechwedd slate quarry.

image copyright Bradley White/Bounce Below

Visitors will be taken deep inside the mountain via train to discover a set of three enormous trampolines, suspended like giant spider's webs.

image copyright Bradley White/Bounce Below

The cavern is illuminated with incredible neon lights, with the trampolines interconnected by stairways and slides. The atmospheric cavern is twice the size of St. Paul's Cathedral and the biggest slide reaches 60ft high.

image copyright Bradley White/Bounce Below

Intrepid visitors will be supplied with cotton overalls and a safety helmet before embarking on their journey into the cavern.