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

Despite time, colonization, and the brutal New Mexican heat, these Pueblo ruins still stand.

This popular pilgrimage site offers a hole filled with holy healing dirt.

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

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

Legends surround this jagged rock formation in the New Mexico desert.

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

A pop-culture attraction outside of Dyersville, Iowa, hits a home run.

A tribute to the twin ideals of religion and patriotism, built by a Catholic priest from rocks, glass, and innumerable found items.

For just a few bucks, this Iowa funicular will let you feel like an 1800s fat cat.

This long unused shot tower on the Mississippi remains a point of pride for a small city in Iowa.

The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

Home to three historic ships from the age of Vikings.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

This chimerical bridge/tunnel appears to dead end right into the sea.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

It houses the remains of a 17th-century version of the Titanic.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A 19th-century artistocrat's mansion, turned into a library, hidden in a modern library.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Baroque celebration of the end of the Great Plague of Vienna.

Op-art architecture designed for happiness.