While Americans are watching fireworks on Friday, people in Northern Wales will celebrate a different kind of freedom. As of Independence Day, the best place in Earth to gain height will be hundreds of feet underground at Zip World's Bounce Below attraction, the world's largest (and only) underground trampoline park.
Park patrons strap themselves into cotton overalls and helmets, descend into a mountain by train, and step into an expansive two-chambered cavern to start the experience. Bounce Below is the result of repurposing the Blaenau Ffestiniog slate mine; instead of mine trolleys, Bounce Below boasts three 60-foot trampoline-like nets connected by walkways and slides. If getting mad air—allegedly up to 80 feet—isn't trippy enough, the amusement glows in Technicolor with a flashy light display.
Sean Taylor, Zip World's commercial director, devised Bounce Below as a means of attracting more people to the already superlative-heavy park: Zip World is home to the world's longest, fastest zip wire and biggest zip zone.
"The surreal experience of Bounce Below cannot be matched as there's nothing like it anywhere else on earth," Taylor said in an interview with Gizmag. "It's essentially a ginormous underground playground and an amazing way to experience a subterranean world in a way never before possible. The best thing is you can do it all year round."
Admission is open to people age five and older and under 265 pounds. The experience lasts one hour and costs £15 (about $26) per person.
If getting to Wales is a bit of a stretch, you can get a similar subterranean experience stateside. Kentucky's Louisville Mega Cavern features extensive underground zip lines and the world's only fully underground aerial ropes challenge course.