The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

There’s a hidden military meme engraved on the World War II Memorial.

Built in the 1850s, this church was of the first five churches constructed in Harper's Ferry.

This claimant to the title of "smallest church in the 48 states" doubles as an equally tiny, quasi-post office.

This shale formation along the Appalachian Trail once inspired the third president of the United States.

This is the cabin from which John Brown and his men launched their fateful war to end slavery on October 16, 1859.

Despite violent work crews and massive delays this abandoned canal tunnel was built to last into the modern day.

The first blast furnace in the United States that used coal and coke fuel instead of charcoal to make pig iron.

The antique hotel still has a jail in the basement, though the cockfighting ring is long gone.

This one-room cabin where the young colonel slept during the French and Indian War.

This beautiful stone arch bridge wasn't even expected to stand for one day, but people have been crossing it for centuries.

A 19th-century Gothic, castle-like statehouse by the Mississippi River.

By day this New Orleans square is for pedestrians, but by night it is a kingdom of kittens.

A house of courtship where the Jazz Age's most storied lovers got their start.

This Garden District mansion was built to be bigger and grander than its original owner's former partner turned rival.

This distinctive Crescent City tradition dates back to the days of horse-drawn carriages.

This cathedral dedicated to Louis IX, sainted King of France, holds many secrets.

Once the site of a Native American harvest festival, this humble clearing later played an invaluable role in the birth of jazz.

The oldest operational cathedral in the U.S. has one shell of a way of projecting speakers' voices.

A prime example of New Orleans' unique architecture these early 20th century homes were built to look like steamboats.

This unique shop is full of memento mori art, antique medical equipment, secret society paraphernalia, and historical relics.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

The second oldest continuously operating bar in Louisiana.

The restaurant keeps a hidden séance room on the second floor and reserves a table for the spirit of the former owner each night.