A pyramid commemorates the birthplace of James Buchanan, the 15th president of the United States

A crumbling World War I fort that is reached through a series of concrete tunnels.

This small Slovenian town has become a magnet for microbreweries.

The world's oldest grape-producing vine has survived four centuries of turmoil and even has its own anthem.

An otherworldly alpine pasture with its own unique microculture that recalls Middle Earth.

A whimsical bridge adorned with decorative dragons.

A miniature train-ride through Slovenia's largest cave system.

This one-time health resort was used by aristocrats around the world.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

This sandwich shop has a century-old elevator behind a sheet of plexiglass.

This lovely picnic spot featuring thunderous jet landings is an aircraft spotter’s dream.

The only place for a truly presidential dram.

This simple stone memorial remembers a secret, Geneva Convention-defying interrogation base from WWII.

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

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

The narrowest house in America is seven feet of pure spite.

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

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

This church built atop a gas station promises to "equip you for the next stage in your life’s journey."

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

Parking garage where Bob Woodward met Watergate source "Deep Throat."

The tunnel under the Capitol Building where Congress takes out its trash.

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.