The USA is home to all kinds of photo-worthy attractions, from the Golden Gate Bridge to the Statue of Liberty.

But there are some sites around the country that are just as weird as they are cool. From an alleged site of extraterrestrial visits to a castle constructed entirely of coral, there’s no shortage of one-of-a-kind, unusual sights to see in the USA.

1. Fremont Troll

2. Area 51

3. Carhenge