1

A city became an unwilling laboratory

In September 1950, San Franciscans went about their lives without knowing that the U.S. military was conducting a biological-warfare vulnerability test around them . During Operation Sea-Spray, bacteria were released into the city’s environment to study how an airborne biological agent might spread through a major coastal city .

The organisms included Serratia marcescens , selected because researchers at the time considered it suitable as a relatively harmless stand-in for something much more dangerous that could be actually used for biological warfare. Residents weren't informed or asked for consent, an aspect of the operation that would raise obvious ethical objections today.

2

Particles were scattered across America

Sea-Spray wasn't the end of large-scale military dispersion experiments. During the 1950s and 1960s, the Army's Operation LAC (Large Area Coverage)used microscopic fluorescent zinc cadmium sulfide particles to investigate how biological-warfare agents might travel through the atmosphere .

The scale was astonishing. The National Research Council later described LAC as the largest test undertaken by the Army Chemical Corps, with experiments spanning an area from the Rocky Mountains toward the Atlantic and from Canada toward the Gulf of Mexico. Related tests took place in places including Minneapolis, St. Louis, Corpus Christi, and Fort Wayne.

3

What really happened at Hawthorne?

Between 1924 and 1933, researchers conducted a famous series of workplace studies at Western Electric's enormous Hawthorne Works, near Chicago. One early question sounded straightforward: Would changing factory lighting make employees more productive?

The answer proved surprisingly complicated. Researchers expanded their work to examine breaks, schedules, supervision, and social relationships. More than 21,000 employee interviews were eventually conducted. The studies helped inspire the idea known as the "Hawthorne effect": that people may behave differently when they know they're being observed.

4

Would you believe everyone else or your own eyes?

Psychologist Solomon Asch devised a wonderfully simple test of conformity in the 1950s. A participant looked at lines of obviously different lengths and had to identify which one matched a reference line. Under normal circumstances, the task was extremely easy.

There was just one catch: nearly everyone else in the room was secretly working for Asch . On selected trials, these confederates confidently gave the same obviously wrong answer before the real participant responded. Many participants went along with the group at least once, despite what they could plainly see. Even more revealingly, later variations showed that simply having someone else break the group's unanimity could dramatically weaken its influence.

5

Scientists created two rival tribes

In 1954, psychologist Muzafer Sherif and his colleagues brought 22 boys, around 11 years old, to a summer camp at Oklahoma's Robbers Cave State Park. The children didn't know that they were subjects in an elaborate experiment .

Researchers separated them into two groups, which became the Rattlers and Eagles, and allowed each to develop its own identity . Then came competitions deliberately designed to encourage rivalry. Hostility escalated quickly. Researchers eventually introduced problems neither group could easily solve alone, such as difficulties involving the camp's water supply. Working toward these shared, or "superordinate", goals helped reduce the conflict.

6

How far would you go if an authority told you to?

At Yale University in the early 1960s, psychologist Stanley Milgram told volunteers they were participating in an experiment about learning. They were instructed to administer increasingly powerful electric shocks whenever another participant answered a question incorrectly .

The shocks weren't real, and the supposed victim was working with the researchers . But the person pressing the switches didn't initially know that. The machine climbed from 15 volts all the way to a menacing 450 volts, and in Milgram's famous baseline experiment, 65% of participants continued to the maximum level when prompted by the experimenter. Some showed considerable distress. Milgram conducted numerous variations with very different results, demonstrating that circumstances mattered enormously.

7

The marshmallow test wasn’t as simple as we thought

Imagine being a preschooler alone in a room with a delicious treat and an agonizing choice: enjoy a small reward now or wait and receive a bigger reward later . Psychologist Walter Mischel and his colleagues used variations of this setup at Stanford beginning in the late 1960s to study delayed gratification and self-control.

Later studies associated children's ability to wait with outcomes years afterward, and the experiment became a pop-psychology phenomenon . But there's an important twist. More recent research using larger and more diverse samples found that the relationship weakened substantially when researchers accounted for family background and childhood circumstances.

8

Facebook experimented with 689,000 news feeds

In January 2012, hundreds of thousands of people unknowingly became participants in an enormous experiment conducted through Facebook. Researchers altered the News Feeds of 689,003 English-speaking users, reducing either positive or negative emotional content and examining what those users subsequently posted .

The study, published in Proceedings of the National Academy of Sciences in 2014, found small changes consistent with "emotional contagion": altering the emotional balance of posts people encountered was associated with corresponding changes in the language they later used.

9

The military tried to build a pigeon-guided missile

Before sophisticated computerized guidance systems, psychologist B. F. Skinner proposed an alternative with feathers. During World War II, his Project Pigeon attempted to train pigeons to help guide weapons toward targets.

The concept wasn't quite as crazy as it sounds. Pigeons could be remarkably good at recognizing visual targets . Skinner trained them to peck at an image displayed on a screen; if the weapon drifted off course, movement of the target image could produce corrective guidance signals through the bird's pecking. The National Defense Research Committee eventually provided $25,000 for the work before dropping the project in 1944. The Navy later revisited the idea as Project ORCON, short for "organic control." Electronic guidance ultimately made the avian alternative unnecessary.

10

The Government really investigated psychic spies

Beginning during the Cold War, U.S. intelligence and defense agencies really did spend years investigating "remote viewing", the supposed ability to describe distant or hidden objects and locations without using ordinary senses .

Various programs eventually became popularly associated with the name Stargate. In 1995, an outside evaluation reviewed roughly two decades of work and concluded that the program hadn't demonstrated sufficiently useful operational intelligence capabilities to justify continuing it. Stargate was terminated.

11

The CIA tried to make a spy cat

During the Cold War, the CIA faced a familiar espionage problem: How could an operative get close enough to secretly overhear a conversation without attracting attention? Someone came up with a decidedly unconventional answer: a cat.

The appropriately nicknamed Acoustic Kitty project investigated whether surgically implanted listening and transmitting equipment could transform an apparently ordinary feline into a mobile surveillance device . Declassified CIA records confirm the project, but officials eventually concluded that environmental and security problems made the technique impractical.

12

Would you stop to help a stranger?

In 1973, Princeton psychologists John Darley and C. Daniel Batson devised an experiment with an almost storybook setup. Seminary students were sent across campus to give a talk. On the way, each encountered a man slumped in an alley who appeared to need help .

Some students were told they had plenty of time; others were told they were already late. And in a brilliant touch, some were heading to give a talk about the biblical Good Samaritan itself. Yet the topic of their speech didn't significantly determine whether they stopped. Time pressure did. About 63% of those who weren’t in a hurry helped, compared with just 10% of those in the high-hurry condition . Some hurried participants passed the distressed stranger while literally on their way to discuss the Good Samaritan.

1

Arizona skips Daylight Saving Time

Image: Christoph von Gellhorn

This is partly true because most of the state doesn’t bother with Daylight Saving Time . They stopped changing the clocks back in 1967. The exception is the Navajo Nation, which stretches into Utah and New Mexico and keeps DST so all its communities stay on the same schedule. Now, as for the smaller Hopi reservation, inside the Navajo Nation, it sticks with Arizona time… Yes, quite confusing if you’re not a local.

2

Georgia isn’t really the Peach State

Image: Jessica Furtney

Georgia loves its peaches, sure, but the state’s top fruit money-maker is actually blueberries . In recent years, blueberries have brought in several times more cash for farmers than peaches. Meanwhile, California grows far more peaches than Georgia ever has. The nickname stuck from the old days when Georgia peaches were famous for their flavor, not their volume. So while the pride is real, the peaches aren’t quite the powerhouse people may think.

3

Nevada didn’t record the hottest US temperature

Image: tommao wang

You probably think of Nevada’s desert heat as unmatched, but the all-time record belongs to California’s Death Valley . In July 1913, it hit a mind-melting 134 degrees Fahrenheit, the hottest temperature not only in America but the hottest ever recorded on Earth!

4

Minnesota doesn’t have the most lakes

Image: Tom Conway

Minnesota proudly calls itself the "Land of 10,000 Lakes," but that’s selling itself short… The real number is closer to 12,000. However, Alaska wins this battle . The state has more than 3 million lakes over five acres in size. In fact, Alaska contains over 40 percent of the nation’s surface water. If you love fishing, kayaking, or just staring at a quiet stretch of water, the true lake capital of America is far up north.

5

Pineapples aren’t native to Hawaii

Image: Christian Joudrey

Pineapples are everywhere in Hawaiian imagery, but the plant actually comes from South America , mainly Paraguay and southern Brazil. Spanish explorers likely brought them to Hawaii in the 1500s after spreading them across the Pacific to places like the Philippines and Guam. Hawaii’s climate turned out to be perfect for growing them and by the 1900s, the islands were producing so many pineapples that the fruit became a symbol of Hawaii itself.

6

Maine isn’t the country’s easternmost point

Image: Chris Henry

If you’re a Geography geek, you’ll love this one. You might picture Maine’s rocky coast as the eastern tip of America, but the actual easternmost point is thousands of miles away, on Alaska’s Semisopochnoi Island in the Aleutians. How is that possible? Well, that’s because it crosses the 180th meridian, putting it in the Eastern Hemisphere. That means part of Alaska technically sits farther east than anywhere in Maine.

7

The biggest US earthquake didn’t happen in California

Image: Lala Miklós

California has suffered some big earthquakes in its history, but the most powerful earthquake in America struck Alaska in 1964 . It hit Prince William Sound with a magnitude of 9.2. It was so strong it shook the ground for four and a half minutes and triggered massive tsunamis. In today’s dollars, the damage would total more than $2 billion. Alaska sits on a collision zone of tectonic plates, making it one of the world’s most seismically active regions.

8

The Everglades isn’t America’s biggest swamp

Image: Joshua J. Cotten

A lot of people picture the Florida Everglades when they think of swamps, but technically, the Everglades isn’t a swamp at all. The real title of the largest swamp in the United States goes to Louisiana’s Atchafalaya Basin , which spans about 1.4 million acres. This swamp has a vast mix of cypress forests, bayous, and marshes, and it’s more than twice as productive as the Everglades when it comes to wildlife and plant life.

9

Big cities aren’t always capitals

Image: Mackenzie Cruz

It surprises people how often the biggest city isn’t the state capital . New York City? Not the capital… Albany is. Chicago? Nope, that honor goes to Springfield. Pennsylvania’s capital isn’t Philly or Pittsburgh, it’s Harrisburg. Even California’s capital isn’t L.A. or San Francisco, it’s actually Sacramento. Out of fifty states, only seventeen have their most populous city as the capital.

10

Alaska isn’t divided into counties

Image: Rod Long

Alaska likes to do things its own way. Instead of counties, it’s split into boroughs , and a massive area known as the Unorganized Borough has no local government at all. People out there don’t pay property taxes, but that freedom comes with challenges, limited services, fewer job options, and tough living conditions.

1

A renovation project saved thousands of lives on 9/11

On September 11, 2001, American Airlines Flight 77 struck the Pentagon at 9:37 a.m., killing 189 people. Few people know this part: the death toll could have been much higher. But there was a renovation project underway at the time of the attacks.

The Pentagon’s five-sided structure is divided into five "wedges," and workers had been renovating them one at a time. Flight 77 struck the wedge that had just been completed. Of the 4,500 people who normally worked in that section, only about 800 had moved back in. Without the reinforced construction and the incomplete occupancy, experts believe the casualties would have been catastrophically higher.

2

The Cold War and the hot dog stand

In the middle of the Pentagon’s five-acre center courtyard once stood a modest hot dog stand. According to a Cold War legend (one still retold by official Pentagon tour guides on every public tour), between the 60s and the 80s, Soviet satellite images tracked large groups of high-ranking military officials converging on that small building at the same time every day.

Soviet intelligence reportedly concluded the structure must be the entrance to some underground bunker in America. In reality, all it did was sell lunch. In 2006, the original stand was torn down, and a sandwich shop was built in its place.

3

Its construction began on September 11th, exactly 60 years before the attack

Builders broke ground on the Pentagon on September 11, 1941. That was exactly 60 years to the day before the September 11, 2001, terrorist attacks that would strike the same building.

Construction had been ordered by Army Brigadier General Brehon Somervell, who wanted a permanent headquarters for the Defense Department to replace its then-17 scattered offices across Washington, D.C.

The project was extraordinarily ambitious: plans called for the world’s largest office building to be completed in just 16 months. In the end, the conception, design, and construction of the entire Pentagon building took a total of 15 months.

4

The same person oversaw its construction and the Manhattan Project

Colonel Leslie Groves of the Army Corps of Engineers took charge of Pentagon construction in August 1941. He worked six days a week and drove his team relentlessly, at one point employing more than 15,000 workers around the clock.

When the Pentagon was finished in January 1943, Groves was assigned to lead the Manhattan Project, America’s secret program to build the atomic bomb . His deputy, Captain Robert Furman, followed him into the Manhattan Project as chief of foreign intelligence. Together, the men who built the world’s largest office building went on to produce the weapon that ended World War II.

5

Why is it shaped like that?

The Pentagon’s iconic five-sided shape was the consequence of a geographic accident. The original site selected for the building, near Arlington Cemetery, **happened to be bordered on five sides by roads. **Architects designed the structure to fit those boundaries, producing a pentagonal floor plan. Then President Franklin D. Roosevelt intervened: worried the massive building would obstruct the view of Washington, D.C. from Arlington, he ordered the site moved to its current location along the Potomac River. But the five-sided design had already been drawn up, and nobody changed it.

6

It was the first desegregated building in Virginia

When the Pentagon was designed in 1941, segregation was the law in Virginia. Original plans called for doubled bathroom facilities: separate ones for Black and white employees, as required by Virginia statute. But President Roosevelt had signed Executive Order 8802 in June 1941, prohibiting racial discrimination in federal employment and government contracting.

As a federal building, the Pentagon was exempt from Virginia law. It became the only building in the state where segregation was not enforced. A fully desegregated federal workplace that opened in 1943. The doubled bathrooms were built anyway, as the plans were too far along to revise, but were never used as separately designated spaces.

7

Its construction was surprisingly frugal and incredibly fast

Ground broke on September 11, 1941, and construction finished on January 15, 1943, just 16 months later. More than 15,000 workers were on site around the clock. Wartime office shortages were so severe that employees moved into completed wings before the rest of the building was finished. Steel was too scarce to use extensively, so builders relied almost entirely on reinforced concrete. The 689,000 tons of sand and gravel required came directly from the nearby Potomac River, cutting transportation costs. The project was budgeted at $35 million, but the final bill was $63 million, which would translate to over $900 million in today’s dollars.

8

You can walk between its farthest points in only 7 minutes

The Pentagon is the world’s largest low-rise office building: 6.5 million square feet of space, which is three times the total floor area of the Empire State Building. Each of its five outer walls is 921 feet long. It has 7,754 windows and 17.5 miles of corridors. Approximately 26,000 military and civilian employees report for work there every day.

Despite that scale, the building’s concentric ring design is so efficient that it takes only about seven minutes to walk between its two farthest points.

9

The man who secretly lived inside its walls

During construction, Colonel Groves drove his deputy, Captain Robert Furman, so relentlessly that Furman rarely left the building. To cope, Furman had contractors build him a small, windowless apartment hidden inside the walls of the Army’s Ordnance Division. In this private room, he could sleep and shower without leaving the premises.

When construction ended and personnel dispersed, knowledge of the hidden room was never passed on to building management. Months later, when Furman returned to Washington on Manhattan Project intelligence business, he found the apartment undiscovered and exactly as he’d left it.

For over a year, he would slip back to the Pentagon, pop open a wall panel, spend the night, and emerge in the morning with his suitcase. He was finally caught in 1943 and forced to surrender the keys. It was never disclosed whether the secret apartment was maintained or eventually absorbed back into the official floor plans.

10

It houses over 30 restaurants, including everyone's favorite chains

The Pentagon feeds roughly 26,000 people a day, and its dining options read less like a military headquarters and more like a mall food court. The main Concourse Food Court, which opened in September 2009 and seats 875 people, is the largest of several dining areas.

Confirmed chains currently inside the building include McDonald’s, Five Guys, Subway, Popeyes, Starbucks (multiple locations), Dunkin’ (two locations), Panera Bread, Taco Bell, Panda Express, Baskin-Robbins, Potbelly, Jamba Juice, and Moe’s Southwest Grill, among others. The building also houses a CVS pharmacy, a florist, a jeweler, and a dry cleaner. In the summer of 2024, Potbelly became the first restaurant to open in the center courtyard. Yes, the very spot where the legendary Cold War hot dog stand once stood.