Verifying the Boundaries of Constantine’s City

The outline of Constantine’s new city, as described in earlier records, is mostly accurate. Ancient writers give us valuable details that support this idea.

(a) Zosimus on the Extension of the Land Wall

According to the historian Zosimus, the land wall of Constantinople was built 15 stadia west of the original wall of Byzantium. A stadion was an ancient unit of length, about 180 meters, so 15 stadia is about 2.7 kilometers.

The original wall of Byzantium stood near the porphyry Column of Constantine, also known today as the Burnt Column. This column was located near the main gate of the old Greek city.

If we go about 2.7 kilometers west from this column, we reach a line close to the Cistern of Mokius and the Cistern of Aspar—two large water reservoirs built on the city’s Seventh Hill. This supports the idea that the new wall built by Constantine reached that far west.

(b) Dimensions in the Notitia Urbis Constantinopolitanae

Another important source is the Notitia, one of the oldest official descriptions of Constantinople. It lists the length of the city as 14,075 Roman feet, and its width as 6,150 Roman feet Sofia Sightseeing.

One Roman foot is about 29.6 centimeters, so:

The length is about 4.2 kilometers.

The width is about 1.8 kilometers.

These dimensions describe the original city of Constantine, not the expanded city built later by Theodosius II.

Not Reflecting the Later Expansion

Although the Notitia dates to the time of Theodosius II (early 5th century), it still describes the smaller city built by Constantine a century earlier. That seems surprising because by then the city had grown larger, and new land walls had been added.

But this may be explained by habit and tradition. People were still thinking of “The City” as the one that Constantine had built. The new Theodosian walls, though important, had not yet changed the way people described or understood the city.

The Original Constantinople

These ancient records show that the original Constantinople was much smaller than the later imperial capital. Its walls were extended only about 15 stadia west of old Byzantium, and its official size remained unchanged in many documents—even when the city itself had grown.

This tells us a lot about how people in the ancient world thought of cities—not just as physical spaces, but also as symbols of empire and history.