Why Are There 5,280 Feet in a Mile?


Why are there 5,280 feet in a mile, and why are nautical miles different from the statute miles we use on land? Why do we buy milk and gasoline by the gallon? Where does the abbreviation "lb" come from? Let's take a look at the origins of a few units of measure we use every day.

The 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.

The Nautical Mile

So if the statute mile is the result of Roman influences and plowing oxen, where did the nautical mile get its start? Strap on your high school geometry helmet for this one. Each nautical mile originally referred to one minute of arc along a meridian around the Earth. Think of a meridian around the Earth as being made up of 360 degrees, and each of those degrees consists of 60 minutes of arc. Each of these minutes of arc is then 1/21,600th of the distance around the earth. Thus, a nautical mile is 6,076 feet.

The Acre

Like the mile, the acre owes its existence to the concept of the furlong. Remember that a furlong was considered to be the length of a furrow a team of oxen could plow in one day without resting. An acre—which gets its name from an Old English word meaning "open field"—was originally the amount of land that a single farmer with a single ox could plow in one day. Over time, the old Saxon inhabitants of England established that this area was equivalent to a long, thin strip of land one furlong in length and one chain—an old unit of length equivalent to 66 feet—wide. That's how we ended up with an acre that's equivalent to 43,560 square feet.

The Foot

As the name implies, scholars think that the foot was actually based on the length of the human foot. The Romans had a unit of measure called a pes that was made up of twelve smaller units called unciae. The Roman pes was a smidge shorter than our foot—it came in at around 11.6 inches—and similar Old English units based on the length of people's feet were also a bit shorter than our 12-inch foot. The 12-inch foot didn't become a common unit of measurement until the reign of Henry I of England during the early 12th century, which has led some scholars to believe it was standardized to correspond to the 12-inch foot of the king.

The Gallon

The gallon we use for our liquids comes from the Roman word galeta, which meant "a pailful." There have been a number of very different gallon units over the years, but the gallon we use in the United States is probably based on what was once known as the "wine gallon" or Queen Anne's gallon, which was named for the reigning monarch when it was standardized in 1707. The wine gallon corresponded to a vessel that was designed to hold exactly eight troy pounds of wine.

The Pound

Like several other units, the pound has Roman roots. It's descended from a roman unit called the libra. That explains the "lb" abbreviation for the pound, and the word "pound" itself comes from the Latin pondo, for "weight." The avoirdupois pounds we use today have been around since the early 14th century, when English merchants invented the measurement in order to sell goods by weight rather than volume. They based their new unit of measure as being equivalent to 7000 grains, an existing unit, and then divided each 7000-grain avoirdupois pound into 16 ounces.


Early 18th-century steam engine entrepreneurs needed a way to express how powerful their machines were, and the industrious James Watt hit on a funny idea for comparing engines to horses. Watt studied horses and found that the average harnessed equine worker could lift 550 pounds at a clip of roughly one foot per second, which equated to 33,000 foot-pounds of work per minute.

Not all scholars believe that Watt arrived at his measurement so scientifically, though. One common story claims that Watt actually did his early tests with ponies, not horses. He found that ponies could do 22,000 foot-pounds of work per minute and figured that horses were half again stronger than ponies, so he got the ballpark figure of 33,000 foot-pounds of work per minute.

Celebrate the Holidays With the 2020 Harry Potter Funko Pop Advent Calendar


Though the main book series and movie franchise are long over, the Wizarding World of Harry Potter remains in the spotlight as one of the most popular properties in pop-culture. The folks at Funko definitely know this, and every year the company releases a new Advent calendar based on the popular series so fans can count down to the holidays with their favorite characters.

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Right now, you can pre-order the 2020 edition of Funko's popular Harry Potter Advent calendar, and if you do it through Amazon, you'll even get it on sale for 33 percent off, bringing the price down from $60 to just $40.

Funko Pop!/Amazon

Over the course of the holiday season, the Advent calendar allows you to count down the days until Christmas, starting on December 1, by opening one of the tiny, numbered doors on the appropriate day. Each door is filled with a surprise Pocket Pop! figurine—but outside of the trio of Harry, Hermione, and Ron, the company isn't revealing who you'll be getting just yet.

Calendars will start shipping on October 15, but if you want a head start, go to Amazon to pre-order yours at a discount.

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Are Halloween Pumpkins Edible?

Diane Helentjaris, Unsplash
Diane Helentjaris, Unsplash

When people visit their local family-owned pumpkin patch around Halloween, they aren’t usually looking for dinner. The majority of the nearly 2 billion pounds of pumpkins cultivated in the U.S. each year are carved up instead of eaten, making the squash a unique part of the agriculture industry. For people who prefer seasonal recipes to decorations, that may raise a few questions: Are the pumpkins sold for jack-o’-lanterns different from pumpkins sold as food? And are Halloween pumpkins any good to eat?

The pumpkins available at farms and outside supermarkets during October are what most people know, but that’s just one type of pumpkin. Howden pumpkins are the most common decorative pumpkin variety. They’ve been bred specifically for carving into jack-o’-lanterns, with a symmetrical round shape, deep orange color, and sturdy stem that acts as a handle. Shoppers looking for the perfect carving pumpkin have other options as well: the Racer, Magic Wand, Zeus, Hobbit, Gold Rush, and Connecticut field pumpkin varieties are all meant to be displayed on porch steps for Halloween.

Because they’re bred to be decoration first, carving pumpkins don’t taste very good. They have walls that are thin enough to poke a cheap knife through and a texture that’s unappealing compared to the squashes consumers are used to eating. “Uncut carving pumpkins are safe to eat; however, it's not the best type to use for cooking,” Daria McKelvey, a supervisor for the Kemper Center for Home Gardening at the Missouri Botanical Garden, tells Mental Floss. “Carving pumpkins are grown for their large size, not the flavor. Their flesh can be bland and the fibers are very stringy.”

To get the best-tasting pumpkins possible this autumn, you’re better off avoiding the seasonal supermarket displays. Many pumpkin varieties are bred especially for cooking and eating. These include Sugar Pie, Kabocha, Jack-Be-Little, Ghost Rider, Hubbard, Jarrahdale, Baby Pam, and Cinderella pumpkins. You can shop for these varieties by name at local farms or in the produce section of your grocery store. They should be easy to tell apart from the carving pumpkins available for Halloween: Unlike decorative pumpkins, cooking pumpkins are small and dense. This is part of the reason they taste better. McKelvey says. “[Cooking pumpkins] are smaller, sweeter, have a thicker rind (meatier), and have less fibers, making them easier to cook with—but not so good for carving.” These pumpkins can be stuffed, blended into soup, or simply roasted.

If you do want to get some culinary use out of your carving pumpkins this Halloween, set aside the seeds when scooping out the guts. Roasted with seasonings and olive oil, seeds (or pepitas) from different pumpkin varieties become a tasty and nutritious snack. Another option is to turn the flesh of your Halloween pumpkin into purée. Adding sugar and spices and baking it into a dessert can do a lot to mask the fruit’s underwhelming flavor and consistency.

Whatever you do, make sure your pumpkin isn’t carved up already when you decide to cook with it. There are many ways to recycle your jack-o’-lanterns, but turning them into pie isn’t one of them. "If one does plan on cooking with a carving pumpkin, it should be intact,” McKelvey says. “Never use one that's been carved into a jack-o'-lantern, otherwise you could be dealing with bacteria, dirt and dust, and other little critters.”