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 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.
Pergamon Bridge
For urban development, such substructions are regarded as particularly useful for providing large open spaces in densely populated inner city areas. This was also the case in Pergamon, as the building of the Serapis Temple required the bridging of an entire section of the River Selinus in order to create sufficient space for a large platform in front of the temple.