Zorbing

Zorbing is the recreation of rolling downhill in an orb, generally made of transparent plastic. Zorbing is generally performed on a gentle slope, but can also be done on a level surface, permitting more rider control. The first zorbing site was established in Rotorua, New Zealand.
The zorb is double-sectioned, with one ball inside the other with an air layer between. This acts as a shock absorber for the rider, damping bumps while traveling. Orbs are lightweight and made of flexible plastic, as opposed to the rigid plastic. Many orbs have straps to hold the rider in place, while others leave the rider free to walk the orb around or be tossed about freely by the rolling motion - water can be added inside, and this is commonly called a "water or aqua ride The inner and outer orb are connected by numerous (often hundreds) small ropes. Orbs have one or two tunnel-like entrances.
Sphereing is also referred to as Orbing or Zorbing, and Zorbing entered the Concise Oxford English Dictionary in 2001 where it was defined as: "a sport in which a participant is secured inside an inner capsule in a large, transparent ball which is then rolled along the ground or down hills".