1

Seattle Underground City

Did you know the remnants of Seattle's original streets are still accessible? Beneath the bustling streets of modern-day Seattle lies the Underground City , a network of subterranean passageways that formed the ground level in the 1800s.

By the end of the 19th century, after the Great Seattle Fire, it was decided to rebuild the city at a higher elevation to combat frequent flooding . So, these original streets, sidewalks, and storefronts were buried, and with it, much of their history.

Guided tours take people through tunnels and ladders and retell real and eerie stories about the history of the Underground City.

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Luray Caverns

Image: Robert Thiemann

Have you ever heard of the underground Stalacpipe Organ ? Not only is it a one-of-a-kind interaction between keyboards and cavern stalactites, but it is also the largest musical instrument in the world, according to Guinness World Records.

This instrument lives in the Luray Caverns, Virginia. It consists of an electric console that taps on these ancient stalactites of varying sizes to produce musical tones. A subterranean wonder, these caverns are also known for their extraordinary size , housing towering stalactites and stalagmites, mirrored pools, and delicate drapery-like calcite formations.

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The Underground Gardens of Baldassare Forestiere

Image: Adrian Botica

This stunning subterranean retreat was built entirely by hand. Tucked under the sun-scorched landscape of Fresno, California, lie the Underground Gardens of Baldassare Forestiere . They are the life’s work of Baldassare Forestiere, a Sicilian immigrant who started digging in the early 1900s to escape the Central Valley's oppressive heat.

Over 40 years, drawing inspiration from ancient Roman catacombs , Forestiere carved an elaborate network of underground rooms, passageways, grottoes, and courtyards that span 10 acres.

A unique masterpiece, the gardens are open with guided tours that lead guests through beautifully designed spaces featuring skylights, arches, and alcoves. This oasis also boasts an array of fruit trees, including citrus, figs, and olives.

4

Ruby Falls

Image: Goodfreephotos_com

Colorful and breathtaking, the Ruby Falls is a geological wonder located inside Lookout Mountain near Chattanooga, Tennessee.

Hidden over 1,000 feet below the mountain's surface, this waterfall cascades 145 feet into a pool , making it one of the tallest underground waterfalls open to the public.

Visitors enter the mountain and descend via elevator. Then, they walk through stunning cave formations such as stalactites, stalagmites, and flowstone. At the waterfall chamber, multicolored lights –powered by renewable energy– illuminate the falls. Lantern-lit tours are also offered as a chance to visit the marvel with a different charm.

5

The Catacombs of Green-Wood Cemetery

Image: Joy Ernst

Arched tunnels of tranquil, sacred vaults lie beneath the Green-Wood Cemetery in Brooklyn, New York. Built in the mid-19th century, these catacombs were designed as a prestigious resting place for the city’s elite , prominent families.

While the catacombs are typically closed to the public, special events are sometimes organized to welcome visitors, such as art expositions, guided history tours, and candlelit tours seasoned with live music and storytelling.

Outside, where the sun does reach, await the serene landscapes and remarkable monuments of the cemetery, which is itself a National Historic Landmark .

6

The Lost Sea

Image: Roberto Nickson

The largest underground lake in America is in Tennessee. Hidden within the Craighead Caverns in Sweetwater, this enormous body of water lies in a cave system filled with fascinating formations, such as stalactites, stalagmites, and rare anthodites, also known as "cave flowers."

A National Natural Landmark, this lake marvels scientists, who are yet unaware of the exact extension of its waters. Those who visit can embark on a boat ride called "The Lost Sea Adventure," first walking inside the cavern before reaching a boat to navigate these ethereal sights.

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Mammoth Cave National Park

Image: Sherin Jacob

The Mammoth Cave National Park is home to the longest cave system in the world . Located in central Kentucky, it extends over 420 miles of explored passages and many more likely undiscovered. Enormous chambers, underground rivers, a labyrinth of tunnels, and gypsum crystal formations can all be found at this site.

The park has been declared a UNESCO World Heritage Site and an International Biosphere Reserve. It also includes over 52,000 acres of protected land on the surface, renowned for its lush forests and diverse wildlife.

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Carlsbad Caverns National Park

Image: Cason Asher

A large bat colony lives in the Carlsbad Caverns National Park in New Mexico, but that’s not its only charm. The park boasts over 100 caves, with its centerpiece being the immense Carlsbad Cavern.

The cavern includes the Big Room, one of the largest underground chambers in North America, spanning 8.2 acres. Visitors can descend via an emblematic natural entrance or by elevator, dropping 750 feet underground. Stalactite formations like the Giant Dome, the Hall of the White Giant, and the Chandelier are some of the caves' breathtaking highlights.

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Indian Echo Caverns

Image: Magda Ehlers

The Indian Echo Caverns, which have been open to the public since the early 1920s, are carved into the limestone of the Appalachian Mountains. Located near Hummelstown, Pennsylvania, this site gets its name from the echoes heard within the cavern’s chambers , which were once believed to be mystical by Native American people in the area.

Unique, immersive sections of the caverns have names like the "Crystal Palace," the "Echo Room," and the "Wedding Room," where, yes, real weddings are sometimes held!

10

Wind Cave National Park

Image: Francesco Ungaro

Wind Cave National Park, located in the Black Hills of South Dakota, is one of the world’s largest caves, but that’s not what it’s most famous for. One signature sight here is the boxwork formation , a rare lattice-like pattern formed by calcite deposits.

The cave system stretches for over 140 miles, though much of it remains unexplored. Popular tours take guests through captivating features like the "Ribbon Room" and the "Crystal Palace."

Why is Wind Cave called that? Mainly due to the "wind" phenomenon that occurs at its entrance. The cave's air pressure causes the entrance to draw in or expel air, depending on atmospheric conditions.

1

There are 52 states in the U.S.

Image: Chris Lawton

Remember that Friends episode where the characters were racing to write down as many state names as they could? When they asked Joey how many he’d gotten, he leaned back and proudly announced: "Fifty-six."

While not many Americans would share Joey’s confusion, believe it or not, some people are lost about the exact number . Many, when asked, reply that the country contains 52 states! Nope, it’s still just 50. People often mistakenly include Puerto Rico and Washington, D.C. as states.

2

The Declaration of Independence was signed by everyone on July 4th, 1776

Image: Ryan Wallace

You’ve seen the paintings—quills raised, scroll unfurled, patriotic ambiance in full bloom. You probably pictured the famous document (scribbled on dramatically aged paper) being passed around the table and filled with names.

But reality was less cinematic . While July 4, 1776, is when the Declaration was adopted, only a few signatures made it on the page that day. Most of the 56 signers added their names over the course of weeks, and some not until August... or even later!

3

The Founding Fathers were all old men with powdered wigs

Image: The New York Public Library

You’d think the Founding Fathers were all 60-something aristocrats in wigs , sitting by candlelight. But many were in their twenties and thirties—Alexander Hamilton was just 21, and James Madison 25. Wigs weren’t as common as Hollywood would have you believe. Most preferred their natural hair, styled with a bit of 18th-century flair.

4

The U.S. Constitution was signed on July 4th, 1776

Image: Tara Winstead

It’s easy to jumble up America’s important dates , but this one’s a whopper. July 4th marks the adoption of the Declaration of Independence, not the Constitution. The Constitution came along in 1787, over a decade later, and was signed on September 17.

5

The Statue of Liberty belongs to New Jersey

Image: Avi Werde

You’d be right to observe that Lady Liberty is surrounded by Jersey’s waters. But there’s a caveat: Liberty Island itself is federal property administered by the National Park Service. And while the island is closer to the shores of New Jersey, it remains under the sovereignty of New York State .

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Benjamin Franklin was a U.S. president

Image: Adam Nir

No! He may have earned his place on the $100 bill, but it wasn’t for being the POTUS. He will always remain, however, one of the most recognizable Founding Fathers . He flew kites in storms, and he founded institutions like it were a hobby. He was a diplomat, inventor, philosopher... basically everything but president.

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The Liberty Bell cracked on the first ring

Image: Joe Richmond

Not exactly. But it sounds poetic, right? A symbol of freedom breaking as it sounded its first call. Except... not true. The Liberty Bell didn’t crack on its first ring. It cracked years after its arrival and was recast twice before the famous fracture, which likely developed in the early 1800s, during a routine toll.

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The Grand Canyon is visible from the moon

Image: Tim Hart

The Grand Canyon is not visible from the moon. At least not to the naked human eye! Neither is the Great Wall of China, as great as it may be. In fact, no man-made structure or geological feature is visible from the moon with the naked eye.

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Walt Disney is cryogenically frozen

Image: Steve DiMatteo

Disney was cremated in 1966, and his ashes rest at Forest Lawn Memorial Park in Glendale. No secret cryo-labs under Disneyland. Just a very enduring urban legend. But the myth persists ; some even think he's buried under Disneyland's Pirates of the Caribbean ride.

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Hawaii is the westernmost state

Image: Roberto Nickson

Alaska is officially considered the westernmost state, even when counting Hawaii. That’s because the Aleutian Islands stretch so far west that some cross the 180th meridian, which is the line that separates the Eastern and Western Hemispheres. And here’s the twist: since those islands wrap around the globe’s edge, they also make Alaska the easternmost state.

11

Hollywood is a city

Image: De'Andre Bush

It might feel like its own world (glamorous, chaotic, full of paparazzi), but Hollywood isn’t its own standalone city. Sure, it has its own sign and red carpet events, which led people around the globe to believe it was independent from L.A., but "Tinseltown" is technically a neighborhood within Los Angeles

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Mount Rushmore is a natural formation

Image: VERONICA LIVESEY

Finally, the unbelievable one. Some tour guides from Mount Rushmore report that tourists have, indeed, looked them straight in the face and asked about the natural phenomenon that carved those profiles into the mountains. Nope —Gutzon Borglum and his team spent 14 years blasting the four former presidents into the rock.

1

Arnold Schwarzenegger’s triple career

Image: E R

Arnold Schwarzenegger lifted his way to bodybuilding fame, then jumped into blockbuster movies, and later into California politics. Each chapter looked completely different from the last, yet he tackled them with the same drive. Few Americans can say they succeeded in three major worlds.

2

Ronald Reagan’s journey from film to the White House

Image: Nathan DeFiesta

Long before he sat in the Oval Office, Ronald Reagan was a rising actor in Hollywood. His path from movie sets to politics took time, but he carried his communication skills with him. By the time he reached the presidency, he was already a familiar face to millions.

3

Robert De Niro’s taste for fine dining

Image: Jakub Dziubak

Robert De Niro made his name in gritty films, yet he had a soft spot for world-class sushi. His partnership with chef Nobu Matsuhisa created a restaurant brand recognized worldwide. The chain brought Japanese fusion to a huge audience and showed that De Niro’s instincts go far beyond Hollywood.

4

Serena Williams is sewing her own path

Image: Aleksandr Galichkin

Serena Williams is known for dominating tennis, but she also made a name for herself in fashion. Her line on HSN featured modern, easy-to-wear pieces that made it to New York Fashion Week. With guidance from industry legends, Serena proved she could design clothes with the same confidence she brings to the court.

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George Clooney’s smooth move into spirits

Image: Max Böhme

George Clooney and his friend Rande Gerber loved tequila so much that they created their own. What started as a private passion soon turned into Casamigos , a top-shelf brand with awards, celebrity fans, and plenty of buzz. The duo went from movie sets to tasting rooms without missing a beat.

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Magic Johnson’s winning streak off the court

Image: Adeolu Eletu

After lighting up the NBA, Magic Johnson built a powerhouse company focused on investing in underserved communities. His deals stretched from movie theaters to restaurants to major teams. His business success soon rivaled his days on the court, turning him into one of America’s most admired entrepreneurs.

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Kate Hudson turns activewear into a powerhouse

Image: Lauren

Kate Hudson co-founded Fabletics and quickly tapped into a growing fitness fashion market. The brand became the fastest-growing label under its parent company, TechStyle Fashion Group, and expanded from online sales into plans for dozens of physical stores. Even with challenges surrounding its parent company, Fabletics kept gathering new fans.

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Will Ferrell builds a comedy hub

Image: 0xk

Will Ferrell helped launch Funny or Die , a comedy site filled with sketches, celebrity appearances, and user videos. It became a big name in online humor and produced shows and specials that fans still talk about. Even through bumps in the road, the company stayed influential in the comedy world.

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Martha Stewart reinvents herself

Image: Ella Jardim

Before becoming the queen of homemaking, Martha Stewart modeled professionally and worked as a stockbroker. She later blended her love of cooking, decorating, and organization into a full lifestyle brand. That leap turned her into one of the most recognizable names in American media.

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Kevin Costner tackles ocean cleanup

Image: OCG Saving The Ocean

Kevin Costner’s big career twist came after an oil spill caught his attention. He invested in technology that could separate oil from water and pushed the idea forward for years. When the Gulf of Mexico spill happened, BP bought dozens of its machines to help with the cleanup. His invention pulled in millions and showed a surprising side of the movie star.