This one-time health resort was used by aristocrats around the world.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

A whimsical bridge adorned with decorative dragons.

A bygone village occupation lives on via this quaint public chalkboard.

The Vermont square that inspired Shirley Jackson's "The Lottery."

Two distinctive homes on a New England village green look like a couple of frosted wedding cakes.

The highest peak in the state of Vermont has some interesting features.

A massive sustainable farm designed by the mastermind behind Central Park.

A beautiful, creepy 19th-century castle stands incongruous in rural Vermont.

Tour the world's largest deep-hole dimension granite quarry, where you can view the plant where gravestones are made and roll a ball down the outdoor granite bowling alley.

Portlandia is the second-largest copper repoussé statue in the United States.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

This little blue house pokes out over the campus of UC San Diego, seven stories high.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Remarkably intact Roman stone fortifications have encircled this Spanish city for centuries.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

A grand New York post office that is home to mailman Santas, scraps of postal history, and a pneumatic mail system.

An annual extravaganza of Broadway theater memorabilia.

This wall on a street corner in Lower Manhattan has been a blank canvas for a rotation of renowned artists since the 1980s.

Possible relics of the ancient Roman city are hidden in this restaurant's façade.

A bit of retro transportation flair preserved in the world's largest department store.

Touching mementoes from those who didn't make it back from World War I still hang in one of New York's oldest bars.

The "Seinfeld" diner.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.