Alabama has a fiberglass Stonehenge. With apologies to Spinal Tap, this one is full-size.

A lush desert oasis in the shape of a narrow crescent.

A playground built by the kids that is a child's wonderland, and a helicopter parent's nightmare.

Despite a fraught and controversial history this African island holds a powerful monument to the tragedy of the slave trade.

A hard-to-reach oasis in a desolate corner of Death Valley National Park.

Geometry and mystery come together in an epic show of octagonal masonry.

This electric green sulphur lake in New Zealand looks like a cartoonish radioactive dump site.

Since ancient times these picturesque springs have been providing bathers with healing waters.

The remains of an encyclopedic sculpture garden later used as an internment camp.

This Irish show cave is said to have been the site of a Viking massacre that claimed 1,000 lives.

Protecting the future of some of the rarest and most misunderstood mammals of North America.

Each spring, a dreamlike carpet of bluebells overtakes the forest floor.

Twin Peaks' real life Double R Diner has been restored to its damn fine television look.

A natural arch carved by a river gave its name to the so-called "Cave of Forgotten Dreams."

A tiny piece of the Moon is embedded in this stained glass masterpiece.

Singapore's landscaping project is home to 18 incredible Supertrees.

A recreated Stonehenge stands in a country field, complete with Easter Island moai heads standing as sentries.

Tracks near this Texas nature site were once thought to support the Creationist belief that man and dino coexisted.

Home to the most complete dodo remains known - one head, and one foot.

The largest self-built castle in the U.S., six decades in the making.

The most isolated mailbox in America lets desert travelers record their passing.

This fantastical waterfall is hidden in a cave located in a cracked cliff.

One of the largest Buddhist stupas in North America is built of concrete designed to last 1,000 years.

The highest paved road in North America winds its way up Mount Blue Sky in Colorado to an altitude of 14,130 feet above sea level.