Home to items never before seen by the public.

This brick-lined pedestrian walkway was once a railway tunnel used during the Civil War.

This stately building in Alexandria, Virginia was built by Freemasons to honor one of their most famous members.

The monument's pointy aluminum tip has been melted down by repeated lightning strikes.

Railroad officials in the early 1900s sought to spare travelers the sight of Roman soldiers’ private parts.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Washington's iconic carousel has a nice piece of Civil Rights history.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

The "lovely red Vega" of the legendary record-settling pilot.

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

A New Jersey state park that was once Napoleon's brother's sprawling estate.

This 25-foot-tall gorilla made his way from the Wildwood boardwalk to a Pine Barrens gas station and deli.

Eccentric concrete mansion and museum designed and built by hand from the inside out.

How this Pine Barrens hill got its name is uncertain, but on a good day the view from the fire tower is crystal clear.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

A museum cafe showcases Native American dishes and indigenous ingredients from across the Western Hemisphere.

Contrary to popular belief, this secluded statue doesn't represent Pennsylvania's founder.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

Where America's first doomsday cult awaited the end of the world.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

These 20-foot sculptures will help guide you from the local train station to the local sculpture garden.

This evocative New Jersey statue memoralizes the Polish victims of a Soviet massacre.

Once considered a marvel of engineering, this 107-mile canal played an integral role in building New York City.