The furlong — furh lang in Old English, literally "furrow long" — is 660 feet. It's the distance a team of oxen pulls a heavy plow through English clay before the animals need to breathe. A man with a rod — a 16.5-foot pole — walks behind them, goading. Forty rods make a furlong. The rod is also called a perch. Same thing.
Medieval fields were strips one furlong long because that's what an ox could do. When it came time to define a mile — the distance between villages, the unit of roads, the thing you'd measure with a thousand Roman paces — the mile had to be built out of furlongs. Anything else would have broken the layout of every field in England.
Eight furlongs worked. Eight furlongs times 660 feet is 5,280. Eight furlongs is also 320 rods, or 80 chains. A chain — 66 feet, invented by Edmund Gunter in 1620, 27 years after the mile was fixed — is one-tenth of a furlong. An acre is one furlong by one chain. The numbers all fit: 640 acres to a square mile, 80 chains to a mile, 8 furlongs to a mile. Every piece interlocks. That interlock is the reason the mile is 5,280 feet, not 5,000. Five thousand would have snapped the whole thing apart.
In 1593, Parliament passed "An Act against the decaying of towns and houses of husbandry" — mostly about preventing landlords from throwing tenants off the land. Tucked inside it was a clause fixing the statute mile at 5,280 feet. The mile had been drifting. Different counties used different miles. The Act standardized it. The number stuck.
Multiply miles by 5,280. That's the conversion. Two miles is 10,560 feet. Ten miles is 52,800 feet. A marathon is 138,336 feet — 26.2 times 5,280 plus the 385 yards the Queen added in 1908. (The yards need their own multiplication: ×3. Then add to the total.)
In the US, the 5,280-foot mile is stitched into the legal fabric of the country. The Land Ordinance of 1785 divided the western territories into townships six miles square — 36 square miles each. Every section inside a township is one mile by one mile. Every quarter-section — the 160 acres Thomas Jefferson thought one family could farm — is half a mile by half a mile: 2,640 feet on each side. The Homestead Act of 1862 gave away quarter-sections. The property lines drawn under that Act are still valid. Walk to the back of a farm in Nebraska, find the survey stake, and the distance from the nearest section corner is measured in feet — but the legal description is in miles. The conversion has been running continuously since 1785.
Quick reference
| Miles | Feet | |
|---|---|---|
| 0.1 | 528 | A city block in Manhattan |
| 0.25 | 1,320 | One lap of a running track: 440 yards |
| 1 | 5,280 | The mile. 20 minutes walking. |
| 3.1 | 16,368 | 5K — well, 5,000 meters. Close to 3.1 miles, not exact. |
| 13.1 | 69,168 | Half marathon |
| 26.2 | 138,336 | Marathon — 26 miles 385 yards |
Frequently Asked Questions
How do I convert miles to feet?
Multiply by 5,280. feet = miles × 5,280. That's the whole formula. If you're doing it in your head, 5 miles = 26,400 feet is a good anchor. Build from there.
Why is the number 5,280 and not a round 5,000?
Furlongs. The furlong is 660 feet. The mile was defined as 8 furlongs because that's how English farming was laid out. 8 × 660 = 5,280. A round 5,000-foot mile doesn't divide by 660 — you'd get 7.57575... furlongs, which is useless for measuring fields. The 1593 Parliament made 5,280 the law, and it's been the law ever since.
Does the US survey system still use this?
Yes. The Public Land Survey System divided everything west of the Ohio River into mile-square sections. A section is 5,280 feet on each side. Property deeds in 30 states trace their boundaries to this grid. Surveyors still set monuments at section corners, still measure in feet, and still convert to miles for legal descriptions. The system has been running since 1785 and will probably run until the country ends.
Engineering Context
Highway stationing is measured in feet. Highway mileposts are measured in miles. The station equation — "Sta 1247+35 = MP 236.24" — bridges the two. Getting the conversion wrong by even 10 feet can misplace a bridge. The CAD file usually handles this automatically, but when a contractor pulls numbers from the plans by hand — which still happens — the ×5,280 is where the error creeps in. Always check the station equation. Length Conversion Guide.
More: feet to miles · miles to meters · miles to km · km to miles · Guide