European castle ruins in an American state park are actually the product of death and grief.

This quirky curiosity shop takes its cues from the world's bazaars.

This woodland architectural installation acts as a camera obscura for the heavens.

A whimsical village of unique treehouses resides in a Washington forest.

A mysterious castle built as a monument to lost love.

Tour the sci-fi-esque reality of governmental disease management.

Breathtakingly blue walls shimmer inside the "Glacier Behind the Town."

This futuristically sylvan church is a glass-enclosed marvel of modern architecture.

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

In the middle of an extremely unforgiving and desolate high desert is the most secret military facility in the world.

Quite simply the largest tree in the world (by volume).

The largest earthwork effigy in the world.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

The remains of an idyllic small town built for the film 'Big Fish' still stand around a rundown main street.

A museum dedicated to the alleged Roswell Incident.

This natural wonder drops 16 stories straight down through rare flora and streaming waterfalls.

The world's longest known cave system.

Take a drunken tour inside the world's largest known geode.

A heavenly experience, right here on Terra Firma.

An underwater city for the dead.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

A technicolor place of worship for Elevationists.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

A beautiful 62-acre Catholic shrine and botanical garden.