Major tourist destination known for its bubbling mud-pools and hot thermal springs.

A New Zealand communications tower stands as the tallest structure in the Southern Hemisphere.

Buenos Aires' city of the dead contains some very famous remains, including Eva Perón.

This historic, palatial theater is now one of the world’s most beautiful bookstores.

Mysterious and ancient carved standing stones.

A lover's walk between hilltop towns, decorated with graffiti love notes.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

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

The home of the Dead Sea Scrolls is an abstract modernist dream.

A dead saint, a deadly poison, and a mysterious holy ooze.

An ancient Egyptian temple in the middle of Madrid, Spain.

This underground church is topped with a 500-foot cross that is seen by many as a beacon of fascist hubris.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

When Croatia became independent of Yugoslavia, the splintering governments left behind these concrete tunnels.

This bridge was the birthplace of a unit of measurement based on a fraternity joke.

Where the alchemists dream of transmuting base metal into gold was actually achieved.

This subtle Berkeley paving stone actually marks off a lawless tube of air that extends into space.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

These aggressively sustainable art homes look like something out of 1970's science fiction.

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

One of America's first dinosaur parks gives a window into Depression-era paleontology.

Every year, over 25,000 monarchs overwinter in Pacific Grove.

A burnt orange monolithic dome structure perched on a hillside near Interstate 280.