Xorbing. The best extreme sport ever. You feel an unearthly sensation when being rolled down a hill in a giant hamster-ball and splashing into a lake. It’s soft, inflatable, has safety harnesses and has 2 huge holes to get in and out. It’s also pretty warm.
But be careful; it’s soundproof and so if you get stuck (like I did) then don’t call for help; gesture for it. I really enjoyed it and reccomend it for ages 7-37 or thereabouts. Anyhoo, it’s great.