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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 .

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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!

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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

Hedy Lamarr

Image: Geoffroy Berlioz

Best known for her 1930s–40s film career, Hollywood icon Hedy Lamarr also co-invented frequency-hopping spread spectrum technology to prevent enemy jamming in WWII. And if you think it’s no big deal, know it’s the basis for modern Bluetooth and Wi-Fi!

While largely overlooked as an inventor at her time, she was posthumously inducted into the National Inventors Hall of Fame in 2014.

2

Sybil Ludington

Image: Taylor Brandon

According to many historians, at just 16 years old, Sybil Ludington rode about 40 miles through the night in 1777 to alert American militia of a British attack on Danbury, Connecticut.

This would make her ride roughly twice as long as Paul Revere’s . While some scholars question the veracity of her story, a statue stands in her honor in Putnam County, New York.

3

Bass Reeves

Image: Pramod Tiwari

Born into slavery in 1838, Reeves became one of the first Black U.S. Deputy Marshals west of the Mississippi. He made over 3,000 arrests during his law enforcement career.

Many historians believe his exploits may have inspired the Lone Ranger character, although his name rarely appears in history textbooks.

4

Mary Edwards Walker

Image: David Trinks

A Civil War surgeon and suffragist, Walker treated soldiers on the front lines and was even captured as a prisoner of war.

In 1865, she became the first woman to ever receive the Medal of Honor. Her unorthodox dress style and fearless activism made her a striking figure in 19th-century America.

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Clara Barton

Image: Kevin Paes

Known as the "Angel of the Battlefield," Barton provided medical care during the Civil War and later founded the American Red Cross in 1881.

Though once a household name, her legacy has faded compared to other, more widely remembered wartime figures.

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Joshua Lawrence Chamberlain

Image: Chris Chow

A college professor turned Union colonel, Chamberlain famously held Little Round Top during the Battle of Gettysburg, a pivotal moment in the Civil War.

He was awarded the Medal of Honor and later became governor of Maine, but his unexpected battlefield brilliance is often overlooked in Civil War discussions.

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Robert Smalls

Image: Ian Hutchinson

In 1862, Smalls, a formerly enslaved sailor, seized a Confederate ship and delivered it to Union forces, securing freedom for himself and his crew.

He later served five terms in Congress, advocating for Black education and civil rights.

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Harvey Wiley

Image: Diana Polekhina

Known as the "Father of the FDA," Harvey Wiley was a chief chemist in the late 1800s whose "Poison Squad" tested various food additives, leading to the 1906 Pure Food and Drug Act.

This law laid the foundation for the FDA and led to the removal of many dangerous substances from consumer products. Notably, it prompted Coca-Cola to eliminate cocaine from its formula in the early 20th century.

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George Washington Carver

Image: Dan Meyers

More than just being associated with peanuts, George Washington Carver developed numerous innovative crop rotation methods and created over 300 uses for peanuts, sweet potatoes, and other plants to help Southern agriculture recover after the Civil War.

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Joe Medicine Crow

Image: Boston Public Library

The last war chief of the Crow Nation, Joe Medicine Crow, completed several traditional war deeds during WWII—including counting coup and stealing enemy horses —and earned both the Bronze Star and the French Légion d’honneur.

Part of his legacy was bridging Native American warrior traditions with modern military service, honoring both cultural heritage and patriotic duty.

1

Thelma from The Family Circus

Image: Angel Sanchez

Here’s a little bit of trivia: cartoonist Bil Keane didn’t just imagine Thelma—he sketched her straight from life, inspired by his own wife. Far from being a background character, she stands as an anchor in a house full of wild little adventurers. College-educated and quick on her feet, she is the quiet balance that keeps the comic’s playful family from tipping over.

Since its debut in 1960, fans of The Family Circus have seen in Thelma not just a mother, but the steady rhythm that turns chaos into charm. She reminds everyone that even in the middle of a circus, there’s always someone holding the tent poles steady.

2

Snoopy from Peanuts

Image: somecomputer

What if a simple old beagle could slip into the role of a daring fighter pilot or a famous novelist without ever leaving his doghouse? That’s the magic of Snoopy.

From the 1950s onward, Charles Schulz gave this iconic, innocent dog a wildly imaginative life, where a simple nap on the roof could turn into a trip across the skies. He rarely speaks, yet every tilt of his ear and twitch of his eyebrow says more than words ever could. Snoopy shows readers that the biggest adventures often happen in our heads, proving that silence can tell a story louder than any punchline.

3

Garfield

Image: Jim Davis, Public domain, via Wikimedia Commons

Who would have guessed that a fat, sleepy cat introduced in 1978 would become one of the sharpest minds in comic strip history? Garfield never bothers chasing mice or protecting the house—he lets others do the hard work while he perfects the art of comfort.

Fueled by lasagna and armed with sarcasm, he turns laziness into a lifestyle. His famous dislike of Mondays isn’t just a joke—it’s a philosophy. Why suffer through the grind when you can nap through it? In his own sly way, Garfield teaches readers that brains sometimes triumph over brawn, especially when pasta is involved.

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Calvin from Calvin and Hobbes

Image: Michał Turkiewicz

What happens when childhood curiosity meets mischievous behavior? Calvin happens. Bill Watterson’s rebellious and cynical six-year-old, born in the 1980s, can transform an ordinary backyard into a galaxy of adventures.

One moment, he’s a space explorer dodging aliens; the next, a philosopher debating life with a stuffed tiger. All his alter egos are playful but also surreal monuments of imagination. Beneath the pranks and wild schemes, Calvin reminds us that messy questions often lead to the brightest discoveries.

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Wednesday from The Addams Family

Image: Jon Tyson

Imagine a child who never giggles at the obvious but instead tilts her head and asks the questions no one else dares. That’s Wednesday. When Charles Addams first sketched her in the 1930s, she wasn’t just another character in a gothic family—she was the sharp thinker in braids.

While her relatives reveled in the bizarre, Wednesday cuts straight to the harsh reality with calm precision. Her curiosity is fearless, her observations unflinching, and her wit so dry it makes readers smirk. In a household full of quirks, she is the quiet compass pointing toward reason.

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Nancy Ritz from Nancy

Image: Tip Top Comics / United Features / Ernie Bushmiller, Public domain, via Wikimedia Commons

Long before "less is more" became a fashion motto, Ernie Bushmiller’s Nancy was already proving the point. With just a few lines, Bushmiller built a character who could provoke laughs sharper than most elaborate gags. Nancy’s jokes landed fast, like little surprise jabs, and her clean, minimalist style made her humor feel universal. Decade after decade, her zingers have stayed as fresh as if they were written yesterday.

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Popeye the Sailor Man from Thimble Theatre

Image: E. C. Segar, Public domain, via Wikimedia Commons

Believe it or not, a cartoon sailor managed to change America’s dinner plates. When Popeye appeared in 1929, kids suddenly wanted to eat spinach, and sales of the leafy green soared by nearly a third.

With his anchor tattoos, squinty eye, and gravelly mumble, Popeye wasn’t exactly polished—he was tough, funny, and unforgettable. Every can of spinach he cracked open turned into instant muscle, proving that strength, humor, and even vegetables could be downright heroic.

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Dick Tracy

Image: R Jangaard

Imagine picking up a newspaper in 1931 and spotting a hard-boiled detective with a futuristic radio strapped to his wrist. For readers of the day, it looked like pure science fiction. Chester Gould’s Dick Tracy wasn’t only solving crimes—he was predicting the kind of technology that wouldn’t appear in real life for decades.

Sharp as a tack, with a no-nonsense style, Tracy blends American gothic with futuristic flair, making every strip feel like a peek into tomorrow’s world.

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Dennis from Dennis the Menace

Image: Alexandra_Koch

On the surface, Dennis seems like every parent’s headache: a freckle-faced kid with a knack for trouble. But dig a little deeper, and you’ll find a sharp mind hiding behind that mischievous grin.

Since the 1950s, his pranks have been less about chaos and more about clever planning and outsmarting the grown-ups. While Mr. Wilson might sigh in defeat, readers can’t help but laugh, knowing Dennis exposes truths adults often tiptoe around. Mischief is his tool; curiosity is his true engine.

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Archie Andrews from Archie Comics

Image: Al Fagaly, Public domain, via Wikimedia Commons

Picture a small town where jukeboxes hum, soda fountains buzz, and Friday night dances are packed with teenagers. That’s the world Archie Andrews introduces us to. With his bright red hair and everyday charm, Archie isn’t a superhero—he’s the kid next door.

Yet, he manages to shine thanks to his relatable stumbles, from juggling homework to choosing between Betty’s sweetness and Veronica’s sparkle. His stories are funny snapshots of small-town America, frozen in time like a favorite old record.

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Mooch and Earl from MUTTS

Image: PNW Production

At first glance, they’re just a cat and a dog. But look closer, and Mooch and Earl are small philosophers wrapped in fur. Patrick McDonnell gave Mooch his playful "Yesh" and Earl his gentle kindness, creating a duo that speaks volumes in just a few words.

MUTTS isn’t about big adventures, it’s about simple, tender moments: a nap in the sun, a wagging tail, a shared silence that feels like music. Through their quirks and quiet humor, Mooch and Earl remind readers that wisdom often comes from uncomplicated friendship.

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Private Carl James "Beetle" Bailey from Beetle Bailey

Image: Mort Walker, Public domain, via Wikimedia Commons

When Mort Walker introduced Private "Beetle" Bailey in 1950, he proved that not every comic hero needs ambition—sometimes a nap is enough. Beetle isn’t just lazy; he turns slacking into a survival skill. While others march, plan, or panic, Beetle drifts away with a smirk, always finding the shortest route around hard work.

Although Camp Swampy is a tough setting, the punchline is clear: Beetle’s effortless way of avoiding obligations is almost genius. Somehow, doing nothing becomes his greatest talent.