The Arch of Carpentras is a Roman triumphal arch from the beginning of the first century AD. It has a single fornix, framed by fluted lesenes and decorated with an archivolt of vine tendrils. At the outer corners there are engaged columns. On the sides there are images of trophies flanked by barbarian prisoners. These trophy reliefs are also found on the short sides of the Arch of Orange, which is however more richly decorated.
The arch was originally located on the city's cardo maximus. Later it was incorporated into the old cathedral as an access door and still later into the episcopal palace (now the courthouse).
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.