The world's biggest shaftless Ferris wheel was put into operation in East China's Shandong province on May 16, 2018. [Photo/Chinanews.com]

Construction of the wheel took three years, and more than 5,000 tonnes of steel was used for the main structure.

"In contrast to typical Ferris wheels, this one has no shaft," said Sun Xuping, head of the construction team.