Pont Flavien, Saint-Chamas · Wikimedia Commons

Pons Flavii

Pont Flavien

BridgeGallia Narbonensis · Saint-Chamas, FranceBuilt 12 BCE

About

A local Gallo-Roman notable named Lucius Donnius Flavos left money in his will around 12 BCE for this single-arch bridge over the Touloubre river, and his family carried out the plan, adding a matching triumphal arch at each end in his memory. Each gate stands about 7 meters tall in the Corinthian order and was originally topped with stone lions, turning an ordinary river crossing into a ceremonial gateway. It carried the Via Julia Augusta, the coastal road linking Italy to Spain through Gallia Narbonensis, and it remains the only Roman bridge anywhere still flanked by both of its original triumphal arches. Traffic used the span continuously for nearly two thousand years until a wartime bombing finally forced its closure to vehicles in 1944.

What happened here

Piers are set on cofferdams — a ring of driven piles, pumped dry, filled with concrete that sets under water. They are built with a cutwater pointing upstream to split the current and the ice. The span above may be stone arches or timber on stone, and timber is not a poor relation: it is cheaper, faster, and replaceable. Roads approach on an embankment so the crossing stays level. Tolls are common, shrines at either end are usual, and the inscription names whoever paid. Floods are the enemy; a bridge is inspected after every big one, and the scour around the piers is packed with rubble. A bridge fixes a town's position for a thousand years, which is why so many are still standing.