Step 1 : Introduction to the question " In 2018, the "Guinness World Records" recognized which bridge as the highest in the world? "
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The Duge Bridge, also called the Beipanjiang Bridge, is a four-lane cable-stayed bridge on the border between the provinces of Guizhou and Yunnan in China. As of 2021, the bridge is the highest in the world, with the road deck sitting over 565 metres (1,854 ft) above the Beipan River. The bridge is part of the G56 Hangzhou–Ruili Expressway between Qujing and Liupanshui. The eastern tower measures 269 m (883 ft), making it one of the tallest in the world, although it is 74 m (243 ft) shorter than the 2004 Millau Viaduct's tallest pier.
The bridge spans 1,340 m (4,400 ft) between Xuanwei city, Yunnan and Shuicheng County, Guizhou and shortens the journey between the two places from around five hours' drive to about an hour.
Construction began in 2011. The bridge was completed on 10 September 2016, and was opened to the public on 29 December 2016. It cost a total of ¥1.023 billion and took five years to build. It was recognized by "Guinness World Records" as the world's highest bridge in 2018.
More Info:
en.wikipedia.org