Why is this here?
Many people visit historical places because they want to see firsthand where an important event took place or where an often-told narrative played out. The allure of these legendary sightseeing spots has everything to do with the historical facts that surround them.
But even in the modern age, the origins of many sites, both modern and ancient, remain a mystery. Experts and enthusiasts have provided theories about these strange places, but there's nothing concrete to satisfy the innate human desire to know the answer to the question: "Why is this here?"
These odd sites can be attractive because of that lack of information. Some tourists come to soak in the atmosphere and relish the sense of mystery that surrounds these places, while others want to concoct their own theories about the site's origin or to create their own fantastical narrative.
Editor's note: This gallery has been updated since it was originally published in May 2014.