Trajan's Bridge

Drobeta-Turnu Severin, Romania

Trajan's Bridge, also called Bridge of Apollodorus over the Danube, was a Roman segmental arch bridge, on the modern Serbian–Romanian border, the first bridge to be built over the lower Danube and considered one of the greatest achievements in Roman architecture. Though it was functional for only 165 years, it is often considered to have been the longest arch bridge in both total span and length for more than 1,000 years.

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