At Washington's Dulles Airport is a satellite museum (no pun intended) with three quarters of a million square feet of aircraft history.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

Check out the 125-pound chocolate reindeer in the back of this candy shop.

A model of a dinosaur that was named for Andrew Carnegie stands outside the museum that also bears his name.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

The souvenir got the company’s founder out of a pretty pickle at the World’s Fair.

America's first public mental health facility.

The hide of Stonewall Jackson's equine sidekick is on display not far from where the ashes of his bones are buried.

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

One of the few working locomotive roundhouses in the United States.

A memorial dedicated to a highly decorated Marine and Korean War veteran, who also happened to be a horse.

This giant, rotating globe was built to celebrate the expansion of a company that makes steam cleaners and pressure washers.

In the parking lot of a fast food restaurant, a statue memorializing a prolific bull elephant.

"Where the ducks walk on fish."

An American flag was erected for every day that passed during the Iranian Hostage Crisis.

These dramatic cola-colored falls have appeared in a poem by Henry Wadsworth Longfellow and a song by Sufjan Stevens.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

This shallow cave got its name from copious amount of human bones found inside.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

World's largest Christmas store.

The 80-foot tire that looms over Michigan's I-94 was once a Ferris wheel in the New York World Fair.

The only surviving prototype for Buckminster Fuller's house of the future.

A sealed test tube said to hold Thomas Edison's dying breath was given to the inventor's friend and mentee, Henry Ford.

The Beaux-Arts aquarium boasts a vast collection of saltwater and freshwater fish on an island in the Detroit River.