An open air haven for tropical monkeys in the damp moors of the English country.

6000-year-old site covered in more than 50 megaliths.

Iceland's largest geothermal mud pool is a little bit haunted and a little bit dangerous.

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

Walk in the footsteps of the gods and straddle two tectonic plates.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Medicinal spa created with the discharge from a geothermal energy plant.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

One of only two commuter aerial tramways in the United States.

Elevated freight railway turned wildly successful urban park.

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

Elvis's own personal tropical hideaway.

A pair of giant roadside arrows are all that remains of a former Route 66 trading post.

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

Experience a charming 1930's version of "infotainment."

The world's longest known cave system.

A sign at the end of the Santa Monica Pier marks the traditional end of the legendary American highway.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

A bizarre roadside attraction and the first instance of miniature golf in the world.

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

High on a hill overlooking Los Angeles lives a world famous, high power conical Tesla Coil.