Gephyrophobia sufferers should turn away now. We’re going to be discussing the longest bridge in the world, and if you have a fear of these water-crossing constructs, some anxiety is going to be inevitable. (Alternately, you might use it as a guide for where not to go.)

Bridges are modern marvels of engineering. Spanning over bodies of water, they can stretch for as little as a few dozen feet to several miles, facilitating the transport of vehicles from one place to another without the need to hop into a boat. Some are suspension bridges, knots of wire and steel without bracing underneath; others are segmented, with support throughout. When someone ponders what the longest bridge in the world is, they may want to consider what kind of bridge they’re talking about.

The Guinness Book of World Records ran into this semantics issue in 2011, when China finished construction on the Jiaozhou Bay Bridge, also known as the Qingdao Haiwan Bridge, near the Shandong Peninsula. The bridge spans an incredible 26.4 miles, with 5200 pillars supporting it along the way. The bridge—which took four years to complete—was so sprawling that it beat the previous record holder, Louisiana’s Lake Pontchartrain Causeway, by more than two miles. Said to be earthquake- and typhoon-proof, it’s one impressive structure.

But the Lake Pontchartrain Causeway is still significant. It’s 23.8 miles over continuous water, while the Jiaozhou Bay Bridge utilizes sea tunnels for parts of the structure and contains multiple lanes. As a result, Guinness refers to the Jiaozhou as the largest “aggregate” bridge in the world, while the Causeway is still believed to be the longest continuous bridge over water.

Those are impressive numbers, but if you don’t require bridges to be needed to navigate over bodies of water, then the longest bridge in the world might be the Dayang-Kunshan Grand Bridge in China. Part of a high-speed railway system, that bridge stretches for 104.2 miles and provides train transport between Shanghai and Nanjing.

If a bridge only impresses—or terrifies—you based on it being the longest bridge in the world without any underlying support, then you might want to investigate the Pearl Bridge beginning in Kobe, Japan. The central part of this 2.4 mile long bridge has 1.237 miles of uninterrupted span.

Of course, length isn’t necessarily directly correlated with the fear factor. If your curiosity over the longest bridge in the world is really over the scariest bridge in the world, you may want to avoid photos of Russia’s Kuandinsky Bridge. Barely wider than a car and with no guardrails, it’s almost a theme park ride, albeit one closed to the public—leaving only the very brave to risk crossing it.

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