Water Ball Zorbing

Zorbing (globe-riding, sphereing, orbing) 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. In the absence of hills some operators have constructed inflatable, wooden or metal ramps. There are two types of orbs, harnessed and non-harnessed. Non-harness orbs carry up to three riders, while the harness orbs are constructed for one to two riders. Double-harness spheres have different slope requirements, and must only be operated in specific locations. The longer runs are approximately half a mile. The first zorbing site was established in Rotorua, New Zealand, by David and Andrew Akers.
Construction
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, for example, of a hamster ball. 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". A typical orb is about 3 metres (9.8 ft) in diameter, with an inner orb size of about 2 metres (6 ft 6.7 in), leaving a 50–60 centimetre (20–24 in) air cushion around the riders. The plastic is approximately 0.8 millimetres (0.031 in) thick. The inner and outer orb are connected by numerous (often hundreds of) small ropes. Orbs have one or two tunnel-like entrances.