The United States of America is pretty massive. When compared to countries in Europe, America is absolutely staggering in terms of its square-mile size. You can travel a few hours through the European countryside and cross through a few different countries. Here, it can take half a day just to make it through one state.

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So, what exactly do we do with all that excess space? Fill it with all manner of strange and interesting pit stops, of course. Road trips wouldn't be nearly as exciting without these alluring, alarming, and sometimes disappointing landmarks. Truth be told, America plays host to some of the weirdest one-offs in the world. Here are 10 of the strangest pit stops you need to check out on your next road trip across the states.

10 Nuclear Waste Adventure Trail (Weldon Spring, Missouri)

Have you ever wanted to walk peacefully and happily over a mound of toxic, radioactive waste without the need for a bulky radiation suit? Yeah, it's not exactly a "dream" scenario that many of us have, but it's exactly what you'll get if you visit the Nuclear Waste Adventure Trail in Weldon Spring, Missouri.

This strange location was created when a problem-solving group decided to entomb an array of hazardous materials rather than drag them miles away into uninhabitable desert-land. The result is an alien-like manmade landscape and what is now known as the highest point in St. Charles County thanks to the rocky elevation.

9 Cano's Castle (Antonito, Colorado)

Anyone who has ever scoured the English countryside or taken a trip to the Irish Isles knows just how majestic a castle can be. There is something so impressive about the stacked stone and imposing man-made structures of the Middle Ages. Colorado has something like that as well, but it's definitely not the Middle Age masterpiece you'd expect.

In the town of Antonito, you'll find Cano's Castle, a massive domed tower-like structure comprised mostly of discarded beer cans and scrap aluminum. The building is adorned with all manner of parts, including wire, hub caps, screen doors, and even bicycle reflectors.

8 Fouke Monster Mart (Fouke, Arkansas)

The tiny town of Fouke, Arkansas holds a dark secret. It's apparently home to a dastardly sasquatch-like beast known as the Boggy Creek Monster. It's said to inhabit a nearby network of creeks and waterways. Many people have claimed to have seen the creature over the years and the legend is so established that a film (The Legend of Boggy Creek) was created and became a bit of a drive-in sensation during its time.

The Fouke Monster Mart pays homage to the town's legendary cryptid and offers all manner of books, gifts, clothing, and other Boggy Creek-inspired goods.

7 World's Only Corn Palace (Mitchell, South Dakota)

Remember the story of the Three Little Pigs, specifically the portly porker who made his house out of straw? Perhaps he'd have been better protected if he'd used a stronger material, maybe something along the lines of corn and grain. Or maybe he should have just hired the architectural crew that built the "World's Only Corn Palace."

The Mitchell Corn Palace, in Mitchell, South Dakota, is truly a spectacle. The massive building is comprised entirely of corn and local grains. This includes the structure, decorations, and even some impressive corn murals. The palace is so famous in the area that it plays host to a variety of events. You can even book and host your own event there.

6 Hole N" The Rock (Moab, Utah)

Ever heard the expression, "have you been living under a rock?" Albert and Gladys Christensen took this expression quite literally by carving themselves a home deep within the mountains of Moab, Utah. The area, which is famous for its Arches National Park and an assortment of sweeping rock formations, plays host to a hidden alcove known as the Hole N" The Rock.

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What looks like a seemingly inconspicuous mountain from the outside houses a... well, house on the inside. The 5,000 square foot home sees guided tours and also includes a gift shop and adjacent exotic zoo.

5 Cadillac Ranch (Amarillo, Texas)

The plains and deserts of Amarillo, Texas are home to one of the strangest spectacles on this list. America's freedom of speech and expression runs deep and rampant through the country, with intriguing art installations and statues peppering state highways and vacant lots all over this beautiful land. But the Cadillac Ranch is truly something special, a completely unique experience in both its style and absolute absurdity.

Born from a group of "artists" called The Ant Farm and a silent partner (Stanley Marsh 3), the row of colorful angled Cadillacs has been confounding Amarillo's visitors for decades. It's definitely something you need to see in person to really appreciate.

4 Enchanted Highway (North Dakota)

Some pit stops and side attractions are so massive that they can't really be considered "stops" at all. Take, for example, the Enchanted Highway. This massive stretch of road, located in North Dakota, is home to a wide array of statues, sculptures, and other art oddities.

During your journey along the 32-mile stretch of highway, you'll come across spectacular metal sculptures that showcase local wildlife, an homage to Teddy Roosevelt, and even a family made out of discarded oil drums. This is a great journey for families and art-lovers alike. There's even a gift shop at the end of the highway which features purchasable miniaturized versions of some of the sculptures.

3 Winchester Mystery House (San Jose, California)

Are you looking for something a little more unsettling to do during your next road trip? Perhaps a tour of the Winchester Mystery House is in order. This iconic landmark in San Jose, California was built by Sarah Winchester, the widow to Albert Winchester of the Winchester Repeating Arms company. After losing her husband, Sarah traveled to San Jose, purchased an eight-room home, and began to renovate the property into the spectacle that it is today.

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The strangeness lies in the layout of the home itself. Sarah believed that the property was incredibly haunted and some say that odd passages and rooms to nowhere were built to confuse spirits. It stands as one of the most haunted places in America.

2 The Georgia Guidestones (Elbert County, Georgia)

Not all of the locations included on this list are exceedingly old. The Georgia Guidestones are relatively young and were only recently erected in 1980. The beautiful granite slabs create an incredibly unique landmark that is both useful and aesthetic. Unfortunately, the use is geared towards the "next wave of humans."

The Georgia Guidestones were crafted as a manual of sorts, should the world go through an apocalyptic event. They feature a subset of guidelines to help reshape humanity. The message is repeated in eight different languages across the stones.

1 Bubblegum Alley (San Luis Obispo, California)

Finally, something completely disgusting. In terms of strange pit stops, this one definitely takes the cake. There are a lot of locations on this list that make you question why the heck they were ever brought into existence, but Bubblegum Alley in San Luis Obispo, California is the absolute epitome of that sentiment.

What likely started out as a nasty habit for locals and tourists has turned into its own art mural of sorts. The walls of this alleyway are completely covered with discarded chewing gum. Patrons have been sticking these wads up for years and you're free to add your own donation to the pile if you can stand to get close enough.

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