Why Are There 5,280 Feet in a Mile?
The basic concept of the mile originated in Roman times. The Romans used a unit of distance called the mille passum, which literally translated into "a thousand paces." Since each pace was considered to be five Roman feet—which were a bit shorter than our modern feet—the mile ended up being 5,000 Roman feet, or roughly 4,850 of our modern feet.
If the mile originated with 5,000 Roman feet, how did we end up with a mile that is 5,280 feet? Blame the furlong. The furlong wasn't always just an arcane unit of measure that horseracing fans gabbed about; it once had significance as the length of the furrow a team of oxen could plow in a day. In 1592, Parliament set about determining the length of the mile and decided that each one should be made up of eight furlongs. Since a furlong was 660 feet, we ended up with a 5,280-foot mile.
Gawd, I've always thought miles were a stupid throwback unit that us Americans use. I spend too much time converting 1610 meters into one mile, which is about a meter to long, but it's much easier to divide into a half mile at 805 meters and a quarter mile at 402 and a half meters. It would be nice to adopt the metric system.