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

The Pope’s secret escape route.

For hundreds of years, automatons moving to metallic music have been marking the passage of time.

The first American department store, and home to the largest operating musical instrument in the world.

These picturesque Hawaiian falls are home to a rare species of fish that uses a special sucker to climb up cliffs.

Vibrant street art created with mixed media.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

A once-glowing grotto at the bottom of Waikapalae Wet Cave.

This blowhole is supposedly caused by a trapped monster.

A series of waterfalls and pools that flow through the 'Ohe'o Gulch and into the ocean.

This black shoreline is made up of exploded lava particles.

These ancient sacred grounds granted amnesty to those who managed to reach them.

A geological mystery on Camelback Mountain.

This historic national park is covered in the stunning ruins of red rock pueblos.

A spiritual vortex among the red rocks in Sedona.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

The highest paved road in North America winds its way up Mount Blue Sky in Colorado to an altitude of 14,130 feet above sea level.

An enthusiastically interactive mining museum that won't let black lung ruin the fun.

Once an unstoppable source of gold and silver, this town came to a grinding stop when the groundwater proved deadly.

A small flooded ghost town with a few scattered structures remaining.

Silver in the hills led to the speedy creation of this boom town and a lack of it saw the town abandoned nearly as quickly.

Abandoned silver mine strewn with wrecked and twisted structures.

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