Porta Negra, detail of upper facade, c. 180, Late Antique, Roman Empire, built to keep Celts out of city of Trier, one of the main Roman capitals. The builders used stone blocks without mortar, clamping them together with iron clamps. Simeon, A Greek monk, transformed the former gate into a church in 1028. Trier, Germany.
Porta Negra, facade, Late Antique, Roman Empire, architecture