The USA is filled with all sorts of unique sights, including hundreds that have been created entirely by nature.
Take a look at the list below to find out more about these bizarre but beautiful phenomenon from around the US.
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10) Bryce Canyon, Utah
The area is dotted with distinctive spiky formations called 'hoodoos' formed over time when rainwater entered cracks and froze, splitting the rocks apart.
9) The Wave, Arizona
Those thinking this naturally sculpted sandstone shute in Arizona looks like the perfect place for a stroll on a summer's day might not be so lucky. Only 20 people a day are permitted to walk on the site, and a lottery is held to determine who has been chosen that day.
8) Desert of Maine, Maine
Usually Maine conjures up images of rocky shorelines and snowy hills but it's not all like that. Believe it or not, the state is home to a 40 acre expanse of sand. It was created by glaciers grinding rocks into silt and it was poor farming practices that caused the sand to take over the landscape.
7) Centralia, Pennsylvania
At one time this small coal mining town was just like any other in America, that is until about 50 years ago when an underground fire began to burn. Despite their best efforts to extinguish it, the subterranean blaze continues to this day and may carry on for another 250 years!
6) Thor's Well
This seemingly bottomless hole off the coast of Oregon appears to be swallowing up the Pacific Ocean but in actual fact it's thought that the hole is only about 20-feet deep.
5) Devil's Tower, Wyoming
In 1906, President Roosevelt made this Wyoming formation the first national monument. But it's legend says that the mountain rose from the earth to protect young boys running from a bear, which then created the vertical marks on the monolith by clawing at it.
4) Hubbard Glacier, Alaska
Even though many of the planet's glaciers are disappearing, parts of the Hubbard Glacier are advancing. It's one of the largest in the state with a face that measures around 6 miles across.
3) Crater Lake, Oregon
Not only is this body of water the deepest lake in America it could also be the bluest. Local legend has it that the mountain blue birds got their vibrant colour after taking a dip in the lake's deep blue waters.
2) Carlsbad Caverns, New Mexico
This attraction is made up of nearly 120 caves, which contain a number of stunning rock formations, the result of mineral deposits that have built up over the last 20 million years.
1) Grand Prismatic Spring, Yellowstone National Park
Yellowstone is known for its dramatic spouting geysers but it's this hot spring that really steals the show. Its rainbow hues are a result of the different bacteria that thrive in each of the spring's various temperature regions.
Which of these natural phenomenon do you think is the most unusual? Let us know in the comments below.
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