Formerly secret, precariously perched boulders.

One of the most remote spots in America and the first protected wilderness area in Nevada, named after an old legend.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

These steeply terraced ruins are a stop along the Inca Trail to Machu Picchu.

A winding, blood-red tunnel of hardened lava navigable by foot.

A fairytale-like medieval church perched atop a rocky cliff on Italy's "Coast of the Gods."

Walk behind a 50-meter-high waterfall.

The summer tourists on these cliffs are thousands of seabirds.

This extinct shield volcano is the lightning rod of the Cascades.

This lake in the Cascades lives up to its name, disappearing down a hole every spring.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Dramatic sea stacks adorn the coast of this small village on the Adriatic coast.

A natural wonder in south Denmark.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

The largest dinosaur trackway in North America is tucked away among this canyon's ghosts and archaeological gems.

The most powerful waterfall in all of Europe.

Where dogs like the rare "Fire-Tailed Border Cocker" run free on the mountainside.

The birthplace of an eccentric alchemist and possible inspiration for the fictional reanimator of monsters.

This rare tortoise skeleton has been hanging around the downtown Los Angeles museum for over a century.

Mortarless walls that stretch for miles are a lovely solution for creating grazing land in the harsh terrain of the Aran Islands.

A remote candy-striped mountain in the Peruvian Andes straight out of the pages of Dr. Seuss.

Ancestral Puebloan ruins, natural arches, and box canyons abound in this seldom-visited corner of Monument Valley Navajo Tribal Park.

This isthmus in the Bahamas narrowly separates the roiling Atlantic from the cool Bight of Eleuthera.

One of the largest ochre quarries in the world, hidden in a limestone landscape.