At its peak around 117 CE under Emperor Trajan, the Roman Empire covered about 5 million square kilometers (around 1.9–1.93 million square miles).

Quick Scoop: How big was it?

  • The empire stretched across three continents : Europe, North Africa, and Western Asia.
  • Roughly 5 million km² made it one of the largest empires of the ancient world.
  • It may have contained between 55–60 million people , with some estimates going as high as 70–100 million, perhaps around a quarter of the world’s population at the time.
  • At its height it ran from Britain in the northwest to the Euphrates and Armenia in the east , and from the Atlantic coast to Egypt and North Africa in the south.

A modern-size feel

  • In area, the empire was smaller than today’s contiguous United States (about 8 million km²) but still enormous for an ancient state.
  • It covered territory that is now part of roughly 30 modern countries (for example Italy, Spain, France, Greece, Turkey, Egypt, and more).

Mini story to picture it

Imagine traveling from rainy Roman Britain, down the stone roads through Gaul and over the Alps to Rome, then sailing past sun‑baked North African ports and finally marching east toward deserts near the Euphrates—all of that was still inside the same empire, ruled ultimately from a single city.

Information gathered from public forums or data available on the internet and portrayed here.