The triple-arched gateway - leading to the Augusteum - Imperial Sanctuary, was built in the early I century AD. Originally propylon was equipped with a bronze dedicatory inscription to Augustus and Latin copy of Res Gestae Divi Augusti - a record of his life and accomplishments (some are still fragments in situ). It was decorated with reliefs and sculptures comemmorating his victories.
Sources:
- Jeffrey Felshman in: Trudy Ring, Noelle Watson, Paul Schellinger eds.: Southern Europe: International Dictionary of Historic Places, Routledge 2013, p.43
- Adrian John Ossi, The Arch of Augustus at Pisidian Antioch: Reconstructing Archaeological Context Through Digital Analysis of an Excavation Archive, American Journal of Archaeology Vol. 120, No. 3 (July 2016), pp. 411-446