A church of bones, decorated with 40,000 human skeletons.

This was once the center of the Birdman cult, and is now a World Heritage Site.

A Roman-style column in Oregon hides a spiral staircase inside.

Two massive rock outcroppings on the Oregon coastline.

The final resting place of soldiers' loyal canine companions.

The most loyal of little dogs, or a Victorian era publicity stunt?

This 17th-century street hidden beneath Edinburgh was once a breeding ground for the black death.

Home of the "true" equator.

Louise Bourgeois' 30-foot-tall steel spider sculpture.

Pilgrimage site for star-crossed lovers.

A tradition unlike any other, this marks the site of the annual Groundhog's Day tradition.

A store full of vintage and indie toys designed to bring out the kid in even the crustiest of adults.

This historic observatory contains the world's oldest refracting lens telescope.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

Nuclear reactor created the plutonium used on Nagasaki.

Tragedy on Little Brewster Island memorialized.

Home of Howard Hughes' Spruce Goose.

This sheep farm has been forever transformed since being built for “The Hobbit” film series.

A rococo retro-futurist future-rustic vernacular between yesterday’s tomorrow and the future that never was.

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

Copenhagen's celebrated theme park and gardens.

Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

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

Famously misunderstood wonder of the ancient world