1

National Mall’s hidden tunnel (Washington, DC)

The National Mall landscape in Washington, DC, is so familiar that it’s hard to imagine anything hidden beneath it, but there is more going on below the surface than most visitors realize.

Beneath parts of the Mall, a network of underground tunnels connects buildings like the Smithsonian Institution Building, a.k.a "The Castle", with other Smithsonian facilities, including the National Museum of Natural History. They’re mainly used for utilities, secure staff access, and behind-the-scenes operations that keep the museums running smoothly.

2

Mount Rushmore’s secret chamber (Keystone, SD)

When you look at Mount Rushmore, the first thing you notice is the four faces of George Washington, Thomas Jefferson, Theodore Roosevelt, and Abraham Lincoln, but there’s more than meets the eye. Hidden behind Lincoln’s head is a secret chamber known as the "Hall of Records," a place visitors have rarely ever seen. It was the idea of sculptor Gutzon Borglum, who imagined it as a grand room to hold important US documents and tell our story as a country. Construction began with that goal, but the project was never completed. Today, the chamber remains unfinished, but it's there, waiting to be visited someday.

3

The Las Vegas sign is in another city (technically, Paradise, NV)

Do you have the classic picture in front of the iconic "Welcome to Fabulous Las Vegas" sign? If you snapped it and then drove to another city, we hate to break it to you, but you weren’t in Las Vegas.

The famous sign, installed in 1959, actually sits a couple of miles outside the city limits. In fact, the sign and most of the Strip are technically located in the towns of Paradise and Winchester, unincorporated communities in Clark County, Nevada, not within Las Vegas itself. And that’s no accident: much of the Strip and its casinos were originally developed outside the city in the 1950s to avoid municipal taxes and regulations.

4

Fragments of the Antarctic ice sheets (Denver, CO)

Did you know that the Mile High City stores miles of ice from Greenland and Antarctica? Ok, but how?

At Denver’s National Ice Core Laboratory, part of the Federal Science Center, the ice is kept at around -32.8°F. Researchers study it not just to understand Antarctica itself, but also to inspect Earth’s history. Some of these blocks of ice are hundreds of thousands of years old, and from them, scientists can reconstruct ancient temperatures, track greenhouse gas levels, and even identify major volcanic eruptions preserved in the layers.

5

The hatch at the top of City Hall Tower (Philadelphia, PA)

Counting the statue of William Penn at its summit, the tower of Philadelphia City Hall rises about 548 feet, making it the tallest municipal building in the United States. But hidden high above the street, the statue conceals a little-known secret.

At its base is a small hatch, originally built to give workers access for maintenance. It offers an incredible vantage point over the city, but getting there isn’t easy. To reach it, you have to climb narrow stairways and walk through tight, elevated passageways. Would you dare give it a try?

6

A 112,544 square-foot underground bunker (White Sulphur Springs, WV)

The tense atmosphere and threats of the Cold War led to the construction of thousands of underground bunkers across the US. And one of the most impressive is right beneath the Greenbrier Resort in White Sulphur Springs, West Virginia.

Buried 720 feet into the hillside, this 112,544-square-foot bunker was created to shelter all 535 members of the US Congress in the event of a nuclear attack. Built between 1958 and 1961, it was sealed behind a 25-ton blast door, and it remained a protected secret for more than 30 years.

7

Catacombs underneath City Market (Indianapolis, IN)

In downtown Indianapolis, the City Market has been a gathering place since 1886, filled with local vendors, cafés, and shops. But there’s more to it than what you see above ground. Beneath the market lies a network known as the City Market’s "catacombs."

Despite the name, the reality isn't quite so macabre; they’re a series of brick archways that once supported Tomlinson Hall, a huge market building demolished in the mid-20th century. Today, this underground space remains as a hidden piece of the city’s past, but unlike many places on this list, it’s occasionally open for guided tours.

8

One of history's biggest art heists (Boston, MA)

We all know Boston as the "birthplace of the American Revolution," home to events like the Boston Massacre and the Boston Tea Party. But there’s another chapter of its history you don’t hear about as often.

Just over 30 years ago, Boston was the scene of one of the biggest art heists in history. In the early hours of March 18, 1990, two men disguised as police officers entered the Isabella Stewart Gardner Museum, overpowered the guards, and stole 13 invaluable works of art, including pieces by Vermeer, Degas, Rembrandt, and Manet. To this day, the case remains unsolved, and a multi-million-dollar reward is still offered for information.

9

One of the quietest places on Earth (Minneapolis, MN)

Where do you think the quietest places on Earth are? You might imagine remote landscapes far from civilization, but one of them is actually right in Minneapolis, Minnesota.

Inside Orfield Laboratories, there’s a room with no windows or natural light, an anechoic chamber that absorbs nearly all sound. That’s right: it blocks almost every noise, making the space even quieter than a vacuum. Visitors say the silence is so intense that you can hear your own heartbeat and even the faintest movements of your body. Simply incredible.

10

A strange law (Los Angeles, CA)

Why would a city actually pass an ordinance saying that licking toads is a bad idea? That’s Los Angeles, a place full of quirks, some charming, some downright strange. Even its laws can be unusual.

The Colorado River toad, found in parts of California, secretes chemicals that can have powerful psychoactive effects on humans. Because of the risks, both possession and use of this substance are illegal statewide. In 1994, cases occurred, including a teacher who was arrested for possessing the toad substance. But Los Angeles went a step further, passing an ordinance that specifically bans licking these amphibians. And let’s be honest, the poor toad probably doesn’t enjoy it either.

1

Area 51

Image: Michael Herren

Location: Nevada

Shrouded in secrecy, this military base has become synonymous with UFOs and government cover-ups. Its official purpose was testing aircraft like the U-2 spy plane and Stealth Bomber, but its classified nature fueled decades of wild speculation, ranging from secret weapons to actual aliens working for the government.

2

Coral Castle

Image: Audric Wonkam

Location: Florida

This massive stone structure was built by a single man, Edward Leedskalnin, using enormous limestone blocks—some weighing 30 tons. According to him, no heavy machinery was ever used during the construction, and he even claimed to know the secrets of the pyramids . To this day, engineers and historians debate how he moved and placed those stones with such precision.

3

Skinwalker Ranch

Image: Jacob Padilla

Location: Utah

This 512-acre property has long been at the center of UFO sightings, cattle mutilations , and alleged portals to other dimensions. The stories were so compelling that, in the ’90s, a private research organization purchased the ranch to try and make some scientific sense of the claims, conducting extensive field studies. However, after nearly a decade of research, they found no conclusive evidence.

4

Mammoth Cave

Image: Ksenia Kudelkina

Location: Kentucky

The world’s longest known cave system has its fair share of unexplored tunnels, ghost stories, and strange air currents. More than 400 miles have been mapped , yet many passages remain uncharted. Researchers have yet to fully understand the cave’s underground ecosystem, and new chambers are still being discovered today.

5

The Marfa Lights

Image: Alexandra Vo

Location: Texas

Reported since at least the late 19th century, floating orbs of light have been seen near this small town with no consistent explanation. Night watchers continue to gather at designated viewing areas along Highway 90, hoping for a glimpse. While scientific studies suggest that distorted car headlights are the most likely cause, many remain convinced otherwise.

6

The Devil’s Kettle

Image: Andrew Ling

Location: Minnesota

This unusual waterfall splits in two—one half flows normally, while the other vanishes into a deep pothole with no known exit. Scientists poured dye, ping-pong balls, and even GPS trackers into the mysterious hole, all to see where the water ends up. While researchers eventually confirmed it rejoins the river underground, exactly how and where remained elusive for decades.

7

Cahokia Mounds

Image: pcrm Dorego

Location: Illinois

Built centuries before Columbus arrived in the Americas, the ancient city of Cahokia featured massive earthen mounds, wooden palisades, and likely formed part of complex trade networks across the continent. Despite having a population rivaling London in the 1200s, according to archaeologists, the city was mysteriously abandoned in the span of a few years. No written records explain its decline, though environmental stress, resource shortages, and internal social factors are often cited as possible causes.

8

Blythe Intaglios

Image: Alexander Schimmeck

Location: California

Similar to Peru’s Nazca Lines, these giant geoglyphs are etched into the desert floor, seemingly visible only from the sky. Created by scraping away dark rocks to reveal lighter earth beneath, the figures are believed to be between 450 and 2,000 years old, depending on the specific design. While their exact purpose remains a mystery, they are believed to have had a ceremonial function.

9

The Spooklight

Image: Ben Griffiths

Location: Missouri-Oklahoma Border

Also known as the Hornet Spooklight, this floating orb has been seen since at least the late 19th century. It appears along a rural stretch of road near the small community of Hornet, Missouri, and Quapaw, Oklahoma. While some theorize it could be caused by car lights from miles away, some sightings predate automobiles.

10

Roanoke Island

Image: Stephen Crane

Location: North Carolina

In the 1580s, an entire colony vanished overnight, leaving behind only the word "Croatoan" carved into a tree. No graves, no remains—just an eerie disappearance that sparked centuries of theories, from disease and starvation to assimilation with local tribes. Modern archaeology uncovered European artifacts at sites associated with Native groups miles away, but no definitive evidence has ever solved the mystery.

1

Elvis Presley

Image: Clem Onojeghuo

Yes, the King of Rock 'n' Roll, who revolutionized music with hits like "Hound Dog," was drafted into the U.S. Army. Presley was offered to serve in the Special Services entertaining troops but chose to serve as a regular soldier.

The most well-known name in entertainment at the time, he was stationed in Germany and earned the rank of Sergeant. There, he met his future wife , Priscilla Beaulieu.

2

Morgan Freeman

Image: Harald Müller

Morgan Freeman, the legendary actor revered for his deep, resonant voice and commanding presence, served as a radar technician in the U.S. Air Force before his acting career took off.

There, he harbored dreams of becoming a fighter pilot. Eventually, though, his time in the cockpit revealed that flying was not his true passion.

3

Humphrey Bogart

Image: Tomas Martinez

The iconic star of Casablanca served in the U.S. Navy during World War I. He worked as a coxswain aboard the USS Leviathan , transporting troops to Europe.

Some versions attribute his signature lip scar —and, by extension, his unique speech—to an injury during his service, though some claim it was from a brawl or childhood incident.

4

Jimi Hendrix

Image: Aditya Wardhana

Jimi Hendrix is widely regarded as one of the greatest guitarists in history. What’s less known about him is that he served as a paratrooper with the 101st Airborne Division back in the 60s.

Even less known is that he enlisted in the Army at age 19 as part of a deal to avoid jail time after being caught joyriding stolen cars. He completed 26 parachute jumps before being honorably discharged a year later due to injuries.

5

Bea Arthur

Image: Ajeet Mestry

Yes, Bea Arthur, one of the beloved Golden Girls , was also a trailblazer as one of the first women to serve in the U.S. Marine Corps during WWII.

Her sharp wit and memorable roles like Dorothy Zbornak earned her multiple awards and the hearts of many Americans. But before acting, she had worked as a typist and truck driver for the Marine Corps, eventually reaching the rank of Staff Sergeant.

6

Bob Ross

Image: https://images.unsplash.com/photo-1662796246357-36ffa59acbca?

Can you believe that the cherished, gentle-voiced host of The Joy of Painting served in the U.S. Air Force for 20 years?

Bob Ross, the soothing icon of creativity and positivity who taught millions how to paint in the famous PBS series, was once a Master Sergeant. He worked as a medical records technician stationed in Alaska. It is said that he once vowed never to yell again after retiring.

7

Mr. T

Image: Skitterphoto

Mr. T, born Laurence Tureaud, is recognized for his role in Rocky III and the hit television series The A-Team. Before his rise to fame, though, he was a military police officer in the 1970s.

There, he stood out in basic training, so much so that he was named the top trainee out of 6,000 recruits. An anecdote retells that he was ordered by his sergeant to chop trees down as a punishment. After one hour, he had chopped down 70 trees and was told to stop.

8

Adam Driver

Image: Venti Views

Actor Adam Driver is known for his roles in films like Marriage Story and the Star Wars trilogy . Few know that he enlisted in the U.S. Marine Corps after 2001 and served for nearly three years before being discharged for a mountain biking injury.

Driver served as a mortar in the 1st Battalion, 1st Marines. After being discharged, he co-founded Arts in the Armed Forces , a nonprofit that brought art programs to military personnel and families.

9

Chuck Norris

Image: Andrea De Santis

Chuck Norris, the action star legend, was once an Air Policeman in the U.S. Air Force. It was there, in fact, where he first began his training in martial arts.

A pop culture icon for his tough-guy image and humorously exaggerated abilities, he was deployed to an air base in South Korea in the late 50s. There, he earned black belts for multiple disciplines in martial arts , including Tang Soo Do and Taekwondo.

10

Johnny Cash

Image: Markus Spiske

Here's another musician who had a career in the military. Johnny Cash, the legendary country singer, was a radio operator in the U.S. Air Force.

The "Man in Black" was a Morse Code listener intercepting Soviet transmissions in West Germany during the Korean War. Allegedly, it was during this time that he bought his first guitar and began writing songs.

11

Paul Newman

Image: Keanu K

The blue-eyed actor from Butch Cassidy and the Sundance Kid also served as a radioman and gunner during World War II. He trained as a pilot but was reassigned as an operator and rear gunner due to colorblindness.

In fact, he avoided flying in the Okinawa campaign due to an ear infection his pilot had. This saved both their lives, and Newman lived on to become a Hollywood legend and philanthropist.

12

Clint Eastwood

Image: Brice Cooper

Clint Eastwood, the iconic actor and filmmaker, was drafted into the U.S. Army during the Korean War. He worked as a swimming instructor for the 35th Infantry Regiment.

He even survived the crash landing of a Navy torpedo bomber with engine problems. He and his pilot had to swim two miles to shore near Point Reyes, California.

13

James Earl Jones

Image: Piotr Makowski

Before lending his iconic voice to Darth Vader and Mufasa, James Earl Jones trained as an Army Ranger and served as a second lieutenant in the Korean War.

After graduating from college in the 50s, he was assigned to the Army's 2nd Infantry Division in Korea. He received an honorable discharge as a first lieutenant in 1955 and went on to pursue the same career his father had: acting.