Burr Oak, Michigan; Village: Location of Burr Oak with St. Joseph County, Michigan: Coordinates: Coordinates: Country: United States: State: Michigan: County: St. Joseph: Area â¢ Total: 1.00 sq mi (2.59 km 2)
The world's largest underground trampoline was unveiled today in caverns which are twice the size of St Paul's Cathedral. Bounce Below is part of Zip World, an outdoor pursuits centre in Blaenau Ffestiniog, North Wales.
It gained popularity in 1950s and 60s and the first world championship competition was held in 1964. The trampoline is the third division of the gymnastics competition, following artistic and rhythmic.