A replica viking ship from the Chicago World's Fair is still in dry dock in an Illinois park.

This house renovated by Frank Lloyd Wright was the centerpiece of a lavish 20th-century estate.

Arguably the best example of an authentic Dutch windmill in the United States, rivaling its counterparts in the Netherlands.

Not to be confused with the iconic New York City skyscraper, this Chicago building is a vibrant hub for artists.

A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.

An acoustic anomaly with a mysterious cause sits in the heart of Tulsa.

These massive mitts are made of 30 tons of devotional bronze.

The oldest experimental corn field in America is still creating better ways to grow crops.

A bizarre house filled with an astounding array of collections.

When you visit his grave, be sure to rub the Great Emancipator's nose for good luck.

Giant six-pack could provide one person a six-pack a day for 3,351 years.

The history of funerals and funerary customs.

This striking art museum holds an amazing series of curiosity cabinets.

A place to eat for on-the-run agents and espionage enthusiasts.

A small abandoned and abused cemetery that has become a magnet for ghost hunters.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

These pretty kitties killed and ate as many as 135 railway workers.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

A Bibliophile's Dream.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

A onetime gangsters' hideaway where you can dine on steaks, fine wines, and cigars just like they once did.

17,400 lbs., 12 feet in diameter, and 29 years in the making.

A Mexican Romeo-and-Juliet-esque legend has given this super-narrow alleyway a reputation for romance.