This hidden gem is bathed in beautiful natural light.

Unfinished monument to peace between Turkey and Armenia, long divided by a dispute over genocide.

The best-preserved ancient theater in the world.

The ornate miniature mansions were built for Istanbul's feathered residents.

This famous city eluded concrete detection until the early 2000's.

This hunter-gatherer architecture is believed to be the oldest religious complex known.

Acres of English cottage gardens, unexpectedly nestled in a Cleveland suburb.

A slab of sandstone covered with mysterious 1,000-year-old rock carvings from a vanished North American culture.

These beautiful wineries were at the center of Lake Erie's "grape belt" back when the Midwest dominated American wine production.

Faces carved into the cliffs create an otherworldly walking trail.

Small, privately owned island divided between Michigan and Ohio with abandoned vacation homes and a derelict lighthouse.

The entrance to this sinisterly named tunnel hides behind a Tim Hortons.

Symbolic attempt to overcome the issues of life.

The longest navigable underground river in the United States is home to countless blind and albino animals.

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

A gregarious Ohio resident has been building his whimsical temple to peace for decades.

This unincorporated community in western Ohio got its peculiar name from John "Daddy" Baker.

Some of the best-preserved specimens of the monumental medieval tombstones found throughout Bosnia and Herzegovina.

A unique collection of Swiss art brut and naïve art displayed in an old warehouse.

A 200-year-old tavern challenges guests to finish a glass of wine while hanging from a ceiling beam.

This eclectic architectural gem played witness to Zurich’s colonial past.

This unique preservation is one of the only taxidermies in the world made with real whale skin.

A symbol of friendship between the mountainous regions of Switzerland and Bhutan.

Over 3km of caverns and caves at the Switzerland-France border contain the largest underground river in Central Europe.