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The highlight of the Florida Panhandle, this 150-mile stretch of mostly undeveloped white-sand beach is a prime example of what the Gulf Coast looked like before human settlement (which, to be fair, can often be seen in the form of high rises in the distance). The National Seashore is not contiguous, but you'll find portions all along the coast: long swaths of sugar white dunes crowned with sea oats, a perfect example of pristine flatland beach.