Ruins of a German Castle on top of a towering stone pillar.

A 30-acre garden inspired by the principles of modern physics.

An ethereal glowing blue ocean cave in Croatia.

Centuries-old bridges grown from tangled roots.

America's most famous piece of self-built architecture.

Hollowed out cedar log tubs set in an ancient towering forest.

Keshwa chaca, among the last handwoven Incan bridges, crosses Apurimac Canyon in Peru.

Rising from the sea like a stone monster.

A giant Troll lurks under one of Seattle's oldest bridges.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

Remants of foundations, streets, and streetcar tracks inhabit the cliffs where a landslide occurred in 1929.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

An Aztec snake god has taken the material form of an apartment complex.

One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

The first declared National Monument in the United States.

Northern Ireland's Brobdingnagian stepping stones.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

Thousands of exquisitely carved stone water storage wells, hundreds of stone steps fill this exquisite medieval stepwell.

Monasteries on rock pillars, once accessible only by frayed ropes.

A serpentine highway twists and turns over the treacherous Norwegian Sea.

An island filled with hundreds of hanging, decomposing, decapitated dolls.

The sound of swaying stalks in this stunning grove has been named a governmentally recognized sound.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

The world's only museum devoted to the wonders of fluorescence.