Da Vinci’s proposal was radically different than the standard bridge at the time. As described by the MIT group, it was approximately 918 feet long (280 meters, though neither system of measurement had been developed yet) and would have consisted of a flattened arch “tall enough to allow a sailboat to pass underneath with its mast in place...but that would cross the wide span with a single enormous arch,” according to an MIT press statement. It would have been the longest bridge in the world at the time by a significant measure, using an unheard of style of design.
Source: Contractor Mag
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