The prototype for all Nazi concentration camps.

The largest source of fossilized insects anywhere.

Only hotel where you can legally launder money.

According to the Guanches, the aboriginal people of the Canary Islands, the king of evil lives inside this volcano.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

A spiritual vortex among the red rocks in Sedona.

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

Climb to the top of the world's largest seated bronze Buddha.

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

Little island known for its massive beachfront "flowerpot" pillars.

The celebrated eyesore created by starry-eyed sweethearts.

Community owned and operated, this property is home to a diverse set of nudists.

The chefs at El Diablo use heat generated by an active volcano to cook the food.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

A wild west cemetery in Tombstone, Arizona, provides a window into the Old West.

Gleaming self-built castle towers made from beer cans and inspired by "Vitamin Mary Jane."

Famously misunderstood wonder of the ancient world

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

Partially collapsed lava tube and cave system complete with concert hall, underground pond, and unique albino crabs.

The New York hotel where tragic visionary Nikola Tesla spent his final hours, destitute and alone but for the pigeons.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

The world's oldest and largest museum of mass transit vehicles.

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

Strange red rock formations that have been attributed to a higher power for hundreds of years.