The stones of this Incan wall complex fit together so well you couldn't fit a piece of paper between some of them.

If you’ve ever seen a picture of Machu Picchu, then you’ve seen a picture of Huayna Picchu—you just didn’t realize it.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

A set of ancient drawings in the desert of Peru that are so massive, many of them can only be fully seen from the sky.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

At this Arctic outpost, get to know members of the indigenous Sámi community and meet their herds.

One of few lasting examples of the brief octagon craze that developed into folly.

Gold Rush ship-turned-hotel buried underneath San Francisco's financial district.

One of the oldest producers of hand-folded fortune cookies still uses its original secret recipe.

The giant pair of sexy legs sticking out the window of this costume store have become its main draw.

San Francisco's oldest surviving monument and meeting place for 1906 survivors.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

Before founding the American Red Cross, Clara Barton had a tremendous humanitarian impact by locating thousands of missing soldiers.

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.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

The national park was once a plantation estate.

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

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

People escaping slavery may have hidden inside a corpse vault.