Building a bridge over water is a daunting task, and despite the many technological progresses, the basics have remain unchanged since ancient times. First a cofferdam is constructed on the riverbed and the water inside this enclosed structure is pumped out, exposing the muddy button. Upon this ground the piers of the bridge are erected.
The historic Charles Bridge in Prague. Photo: Adisa/Shutterstock.com
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How Medieval Bridges Were Built—An Animation
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