Earth's curve tilts bridges

Really. The top of towers of the Verrazano - Narrows Bridge at the mouth of the Hudson river in New York City are tilted almost two inches further apart than the base thanks to the curve of the Earth's surface.

Actually, there are a lot of amazing things about that not-so-famous bridge.

When it opened in 1964, at 4260 feet it was the longest suspension bridge in the world, exceeding the Golden gate completed in 1937, by 60 feet. Today it's the longest single span in North America and the seventh longest in the world. (The longest is the 6,529 foot Akashi-Kaikyo Bridge in Japan, completed in 1998.)

The Verrazano - Narrows Bridge contains enough concrete to construct a single lane highway from New York to Washington, and if the wires that make up the suspension cables were laid end-to-end they would reach 143,000 miles, more than halfway to the moon.

On hot days, the double-decker road bed expands almost six feet and sags 12 feet lower, something that ships passing underneath have to consider. In fact, the Queen Mary 2 had to modify its smokestack to pass under the bridge.

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