A historic hotel library in Indiana hides more than a few secrets on its shelves.

The world's largest collection of mechanical puzzles is a cornucopia of analog bafflers.

The building is topped by a Statue of Liberty statue whose torch has stayed burning since the museum opened.

This magnificent Cincinnati graveyard is also a popular public park.

This humble star-gazing center touts itself as the "Birthplace of American Astronomy."

This psychedelic tromp l'oeil seems to be beckoning drivers to crash into a wall.

This titanic steel chain linking two buildings was installed without permission but instantly beloved.

This modern castle sat empty for decades before a fire inspired its builders to complete its luxury halls.

This mansion was made famous by its colorful cast of owners and location along the Sante Fe Trail.

This museum presents a dogged pursuit of 500 years of veterinary history.

This "little gallery in the middle of nowhere" is housed in a 170-year-old horse barn in the Missouri Ozarks.

A gem in the small Missouri town where Winston Churchill coined the term "Iron Curtain" and effectively began the Cold War.

The ruins of a 19th century shelter run by the Independent Order of Odd Fellows.

This historic motel standing at the "crossroads of America" offers a radio in every room and was saved by local protesters.

Two hundred tons of pioneer artifacts were painstakingly recovered from a shipwreck at the bottom of the Missouri River.

The mayor made the declaration in 2004.

A wild west land agreement was etched right onto this historic Idaho stone.

Despite his legacy of work in Spain, Cuba, and Florida, the larger-than-life writer's grave is a simple affair tucked in an Idaho cemetery.

A legal loophole makes it possible to get away with murder within this 50-square-mile section of Yellowstone.

This town is home to the world’s largest arch constructed entirely of elk antlers.

At the time of its completion, it was the tallest dam in the world.

The high point on the 16th president's eponymous roadway is marked by a massive version of his head.

Population: 1.

A popular rock that acted as a waymarker for American pioneers.