London Eye

"The entire structure is 135 metres (443 ft) tall and the wheel has a diameter of 120 metres (394 ft). When erected in 1999 it was the world's tallest Ferris wheel. Its height was surpassed by the 160 m (520 ft) Star of Nanchang in 2006, the 165 m (541 ft) Singapore Flyer in 2008, and the 167.6 m (550 ft) High Roller (Las Vegas) in 2014. Supported by an A-frame on one side only, unlike the taller Nanchang and Singapore wheels, the Eye is described by its operators as "the world's tallest cantilevered observation wheel"."