A Ferris wheel (also called a Giant Wheel or an observation wheel) is an amusement ride consisting of a rotating upright wheel with multiple passenger-carrying components (commonly referred to as passenger cars, cabins, tubs, gondolas, capsules, or pods) attached to the rim in such a way that as the wheel turns, they are kept upright, usually by gravity. Some of the largest modern Ferris wheels have cars mounted on the outside of the rim, with electric motors to independently rotate each car to keep it upright. These cars are often referred to as capsules or pods.
The original Ferris Wheel was designed and constructed by George Washington Gale Ferris Jr. as a landmark for the 1893 World's Columbian Exposition in Chicago; although much smaller wooden wheels of similar idea predate Ferris's wheel, dating perhaps to the 1500s. The generic term "Ferris wheel", now used in American English for all such structures, has become the most common type of amusement ride at state fairs in the United States.The tallest Ferris wheel, the 250-metre (820 ft) Ain Dubai in the United Arab Emirates, opened in October 2021 but is no longer in operation. The current record holder since 2014 of a Ferris wheel in operation is the 167.6-metre (550 ft) High Roller in Las Vegas, Nevada, which opened to the public in March 2014.