Mile (mi)
The mile is a unit of length in the imperial and US customary systems, equal to exactly 1,609.344 meters or 5,280 feet. It is the standard unit for measuring road distances and speed limits in the United States, the United Kingdom, and a handful of other countries. Whether checking a car's odometer, training for a marathon, or reading a highway sign, the mile is one of the most recognisable units in the English-speaking world.
Definition
One international mile equals exactly 1,609.344 meters, 1.609344 kilometers, 5,280 feet, 1,760 yards, or 8 furlongs. It must not be confused with the nautical mile (1,852 meters), which is used in maritime and air navigation and is based on one minute of arc of latitude. The survey mile, slightly longer at approximately 1,609.347 meters, was used in US land surveying until 2023.
History
The mile originates from the Roman mille passus ("a thousand paces"), where each pace consisted of two steps and measured roughly five Roman feet, making the Roman mile about 1,480 meters. When the unit reached England, it was shorter than the local furlong-based system, so in 1593 an act of Parliament under Queen Elizabeth I redefined the English mile as exactly 8 furlongs, or 5,280 feet, to reconcile the two systems. This statute mile remains the standard today. In 1959, the International Yard and Pound Agreement fixed the yard at exactly 0.9144 meters, which set the mile at precisely 1,609.344 meters. Most countries abandoned the mile during metrication in the 19th and 20th centuries, but the US and UK retained it for road distances.
Common Uses
In the United States, all road signs display distances in miles and speed limits in miles per hour. Vehicle odometers in the US read in miles, and fuel economy is expressed as miles per gallon. Runners train for mile-based race distances, and the four-minute mile remains one of the most famous benchmarks in athletics. In the United Kingdom, road distances and speed limits use miles despite the country otherwise having adopted the metric system. Air travel distances between cities are often quoted in miles for frequent-flyer programmes.
Did You Know? Facts About Mile
- The four-minute mile was first broken by Roger Bannister on May 6, 1954 at Oxford - the current record stands at 3 minutes 43.13 seconds, set by Hicham El Guerrouj in 1999.
- The Roman mile was about 1,480 meters, roughly 8% shorter than today's statute mile.
- The phrase "a miss is as good as a mile" dates back to the 17th century and means a narrow escape is no different from a wide one.
- The United States has approximately 4.19 million miles (6.74 million km) of paved roads.
- Iceland, despite using the metric system, still refers to old Icelandic miles (about 11.1 km each) in rural folklore and traditional place descriptions.