This highest bridge in the world spans such a great chasm that it had to be established using rockets.

This Prague museum collects brutalist relics and memories from the country's former Soviet rule.

This Massachusetts home was the first to have a telephone line and its own phone number: 1.

Once described as the "Eagle's Nest," this ruined ancient city rests on a remote mountaintop.

One of the world's oldest universities houses an incredible collection of anatomical models, mummified body parts, and human bones.

One of America's first planned communities is preserved in a state park.

The bank that helped fund the Mexican-American War and the purchase of Alaska met its downfall after helping Augusto Pinochet launder money.

A fairytale-like medieval church perched atop a rocky cliff on Italy's "Coast of the Gods."

A bas relief commemorates the "Nuns of the Battlefield" who cared for soldiers on both sides of the conflict.

A quirky and charming restaurant founded by artists.

A no-frills, DIY nature preserve manned by a U.S. expat who has dedicated his life to turtle conservation.

A memorial to the tens of thousands of Irish who fled to North America during the Great Famine.

Before Metro, Washington had a robust streetcar network—and you see the remains of this infrastructure if you know where to look.

The people's champion of the French Revolution was so overcome by grief at his wife's death that he exhumed her in the dead of night to make one final replica of her face.

A former top secret nuclear fallout shelter now operates like a hotel stuck in the Cold War.

Said to be one of Sweden's most haunted places, this vicarage once even attracted a ghost-busting priest.

This giant power line tower is a robot that can express its moods in neon.

Despite the groans of archaeologists, this astounding groups of Bronze Age petroglyphs have been painted red for tourists.

This constantly evolving art space saved an Italian town from its own crippling reputation.

Running under an entire mountain, the longest highway tunnel in North America is kept fresh using portal fans and jet fans.

This small city where almost everyone lives in the same building can only be reached via North America's longest tunnel.

This historic stone bridge has an entire neighborhood clinging to its sides.

The remains of a failed attempt at medieval nerdery are hidden deep in the woods of Virginia.

This futuristically sylvan church is a glass-enclosed marvel of modern architecture.