After the Late Antique period, the city of Attaleia assured its continued safety against threats coming from the east by renewing and strengthening its defenses. As a result, the appearance and character of the city walls changed considerably from what they had been in Roman Imperial times. These changes affected city gates the most, as they constituted the weakest points both structurally and strategically, and many of the Roman Imperial era gates were closed. The pulling down or partial or complete destruction of these city entrances already in the Early Byzantine period, changed the fabric of those parts of the city near the walls until the end of the Ottoman period. The most extensive destruction of the city walls, the remains of which can be seen on several towers and curtain walls today, came about during the systematic demolitions of the early 20th century. This study deals with a monumental Roman city gate that has been recently revealed. An arched entrance which was built very close to and possibly at the same time as Hadrian’s Arch, this gate was completely closed during consolidation of the fortification walls in the Early Byzantine period in a manner that concealed it from the exterior. Due to the weakness of the Roman Imperial era curtain wall in which it is located, this gate, which was decorated with pilasters and capitals on both sides, was given the form of a small arch rather than a simple city entrance.