When we talk about the architecture of Philippopolis at the time of the Roman Empire we mean the period of 2nd century AD. This was an era of peace for the provinces and Rome itself. A time when attention to the arts was paid and when the architecture was highly esteemed. During this century, the Empire was ruled by the "Five Good Emperors" of the Antonine dynasty.
Roman architecture was influenced by Hellenistic and Etruscan cultures. For a long time, it followed the typical Ancient Greek ways of construction and admired them.
What were the innovations in construction and architecture introduced by the Romans?