17th century streets hidden under Edinburgh were once a breeding ground for the black death.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

This abandoned amusement park was built on a site with a dark history.

A particularly creepy abandoned hospital that sparks interest for lovers of the supernatural.

An alternate history park where the Union Army loses the war... to dinosaurs.

This scenic Maryland park was the site of one of the worst prison camps of the Civil War.

The land is home to swimming ponies and a legendary 18th-century treasure.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

The walls of the iconic dome are hollow and have a secret stairway.

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

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

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

The romance of early commercial flight still fills this Art Deco destination.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

At 207 feet, one of the world's longest continuous escalators.

Walk through the history of American pop culture.

A museum dedicated to exhibiting remarkable outsider art.

This abandoned dream castle and its cemetery look out over the city that once inspired their creation.

The largest burial mound in the United States holds the remains of prehistoric West Virginians.

Despite its lavish ornamentation, and wholesome lifestyle of its devotees, this mountain commune has faced its share of issues.

Beyond the usual stories that attend old prisons, this one has deep bloody undercurrents.

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