The London Eye is a giant Ferris wheel on the south bank of the Thames River. The structure is 145 meters (443 feet) tall. When it opened to the public in 2000 it was the world's tallest Ferris wheel; it is currently (2017) the 4th tallest, the current tallest being the Star of Nanchang in China at 165 meters (541 feet). It's the most popular paid tourist attraction in the United Kingdom with over 3.75 million visitors yearly. The attraction was formally opened by then Prime Minister Tony Blair on 31 December 1999, but was not opened to the public until 9 March 2000 because of a mechanical issue.

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