Hide from the tourist hordes in these relatively unknown, and unguarded lava caves.

A controversial memorial at the place where Captain Cook met his violent end.

These ancient sacred grounds granted amnesty to those who managed to reach them.

A true treehouse near Hawai'i Volcanoes National Park.

The southernmost point in the United States is a beautiful place to look at but a deadly place to wade in.

A beach made of semi-precious green sand on the Big Island of Hawai'i.

Two volcanic lakes in an enormous crater formed in a prehistoric eruption.

Travel deep inside of Europe's second largest glacier in the world's largest man-made ice cave.

This simple badlands butte is the highest point in North Dakota and may be the only high point to charge admission.

A rancher expanding a natural spring for his cattle came up with bones – lots and lots of them.

Other-worldly rock formations and ancient fossils abound in this unique stretch of Nebraska badlands.

America's largest man-made forest was planted in an effort to bring back the past.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

Hidden behind Lincoln's head is a 70-foot-long chamber containing enamel plates documenting American history, sealed in a teakwood box in a titanium vault.

A place where the laws of nature seem to have gone completely berserk... but of course haven't.

An abandoned railroad tunnel is now filled with bioluminescent bugs.

A collaboration of art and ornithology mourns the calls of Sydney's lost birds.

This natural sea cave hides a small wonderland of natural turquoise beauty.

These strikingly barren, rolling red hills were caused by bad farming practices.

Where manatees are the snowbird vacationers in these balmy Florida springs.

Rustic natural hot springs in the deciduous rain forest.

Make your reservation to have coffee with some kitties.

The oldest (maybe) swimming pool in Iceland is a stunning oasis built into the side of a lush hill.

This wrecked airplane has been sitting on a black sand beach since the 1970s.