Why the Mile Equals 1,000 (Roman Paces, That Is)

Ever wonder why we call it a mile? The answer marches straight out of ancient Rome. The word comes from mille passus—Latin for "a thousand paces"—the distance a Roman legion could cover in 1,000 double-steps.

But here's the catch: a Roman pace wasn't just one step. It was a double-step, measured from where your left foot landed to where it landed again. Left, right, left—that's one pace, roughly 5 Roman feet or about 4.85 modern feet.

How Roman Marches Became Modern Miles

Do the math: 1,000 paces × 5 Roman feet = 5,000 Roman feet per mile. When the Romans standardized their measurements under Agrippa in 29 BC, they locked this distance into law. The Roman mile worked out to about 4,854 modern feet—shorter than today's 5,280-foot mile, but close enough that the name stuck.

Roman roads spanned over 250,000 miles at the empire's peak, all measured in milia passuum. Stone markers called milestones (yes, that's where we get the word) stood every Roman mile, telling soldiers and travelers how far they'd come and how far they had to go.

From Legion Boots to Your Odometer

When the Roman Empire crumbled, their measurement system didn't. Medieval England inherited the mile, though they tweaked it over centuries. In 1593, Queen Elizabeth I's Parliament officially set the mile at 8 furlongs—5,280 feet—to match agricultural land measurements. That's the mile we use today.

The Romans gave us more than roads and aqueducts. Every time you check your car's mileage or run a 5K (3.1 miles), you're using a unit of measurement born from the cadence of Roman sandals on stone roads. Mille passus: one thousand paces that marched through two millennia and counting.