Understanding the Location of Byzantium’s Ancient Gate

The historian Zosimus makes a statement that, when read alone, can be misunderstood. His words suggest that the ancient gate of Byzantium may have stood west of Constantine’s Forum. This would mean that the Forum was built east of the gate, inside the city walls built by Emperor Severus.

According to Zosimus, people entered the porticoes of Severus and exited the old city by passing through arches. These arches stood on the east and west sides of Constantine’s Forum. This layout would only make sense if, when moving from east to west, the structures were arranged as follows:

Constantine’s Forum

Porticoes of Severus

The old gate of Byzantium

If this were true, then when Zosimus said the Forum stood “where the gate had been,” he might have meant that the porticoes between the Forum and the gate were too short to be worth mentioning Sofia Daily Tours.

Conflicting Historical Sources

However, reading Zosimus in this way causes problems. It contradicts other historical sources:

Theophanes, a later historian, provides a different account that doesn’t support Zosimus’s version.

Hesychius of Miletus clearly states that the wall of Byzantium did not extend beyond the Forum of Constantine. In his words, the wall reached “not beyond the emperor’s market” (Forum).

Even though it is less critical, the Anonymus and Codinus also provide a different explanation. They say the circular shape of the Forum was inspired by the shape of Constantine’s tent when he laid siege to the city. This would place the Forum outside the old city walls.

Modern Scholars’ Interpretation

Modern scholars such as Lethaby and Swainson propose a clearer arrangement of the city’s layout. They place the Forum of Constantine directly between the porticoes of Severus on the east and the ancient gate of Byzantium on the west. According to their interpretation:

The western arch of the Forum stood on the site of the old gate.

A person inside the Forum could go east to enter the Severus porticoes, or west to exit the city through the old gate.

This explanation helps to align Zosimus’s account with the archaeological and historical evidence. It shows how Constantine restructured the city, using existing features like the Severan gate and adding monumental spaces such as his Forum.

A City of Layers

Constantinople (originally Byzantium) was a city shaped over centuries. Each emperor, including Severus and Constantine, left their mark by rebuilding, expanding, and adapting existing structures. The debates about the location of the ancient gate and the placement of the Forum show how deeply architecture and imperial ambition were linked in the making of this historic capital.