Miles to Feet

The odd number is a compromise between two older systems. English farmers measured fields in furlongs, the length of a plowed furrow, set at 660 ft. The mile inherited from the Romans was 5,000 Roman feet, and English versions of it varied. In 1593 an Act of Parliament under Elizabeth I defined the mile as exactly eight furlongs, which made it 8 × 660 = 5,280 ft and kept the agricultural units intact.

The furlong survives in horse racing, where the Kentucky Derby is 10 furlongs, 1.25 miles, or 6,600 ft. Since the international agreement of 1959 the foot is 0.3048 m, so a mile of 5,280 ft is exactly 1,609.344 m.

Drag racing runs over a quarter mile, 1,320 ft, while many modern tracks use an eighth mile of 660 ft or the 1,000 ft distance of top-fuel classes. Denver's nickname, the Mile High City, comes from a marked step on the state capitol at 5,280 ft above sea level. A sign saying a turn is 0.1 mi ahead means 528 ft, about the length of a long city block.

Bridges and runways are given in feet in the US: the Golden Gate Bridge is about 8,981 ft long including approaches, roughly 1.7 miles. Aviation weather reports visibility in statute miles, so 3 mi visibility is 15,840 ft.

Ships and aircraft measure in nautical miles, which are about 6,076 ft, not 5,280. Using 5,280 for a nautical distance underestimates it by around 13%. For conversions between the two, see nautical miles to miles; for kilometers and yards, the unit converter has every length.