These ruins of a pre-Columbian cliff village are among the most beautiful and well preserved in New Mexico.

A small metropolis of Pueblo cave dwellings have been carved right into the hillside of this national monument.

These Pre-Columbian petroglyphs contain representations of birds, deer, hunters, and even some early Native flute players.

A multi-storied adobe complex has been inhabited for more than a thousand years.

A phenomenal assembly of pueblos in New Mexico is the most complete example of ancient ruins north of the border.

Twice a year, visitors can tour the desolate site that birthed the Atomic Age.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

Locals dubbed it the "Owl Building" because of its bird-like appearance.

Where commuters walk through remnants of an ancient Greek necropolis.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

The final resting place of American icon Buffalo Bill, and a museum that aids in telling his tale.

The spot in the Mile-High City that's exactly 5,280 feet above sea level (at least for now).

One of the greatest heroes of the Titanic tragedy came from humble beginnings to this beautiful home.

Wall to wall taxidermy at Denver's oldest and most exotic steakhouse.

The highest bridge in America was built for an almost unnervingly small amount of money.

Great place to have a drink and a bite to eat in an atmosphere laden with New York's Bohemian past.

There’s a secret bunker inside the Brooklyn Bridge, but the city won’t say where.

A favorite Paris bar for U.S. expats, including Gershwin, Hemingway, and James Bond.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.