Pergamon Bridge

The Pergamon Bridge is a Roman substruction bridge over the Selinus river (modern Bergama Çayı) in the ancient city of Pergamon (today Bergama), modern-day Turkey. The 196 m (643 ft) wide structure, the largest of its kind in antiquity, was designed during Hadrian's reign (AD 117–138) in order to form a passageway underneath a large court in front of the monumental "Red Basilica" temple complex. The two intact tubes, which consist of supporting walls covered with barrel vaults, still serve their purpose to this day.