The ghostly remains of an accidental sea.

This abandoned Navy base was transformed into an off-grid alternative living community for thousands of people.

The skyline of Montreal includes the silhouette of an unexpected fruit-shaped Canadian staple.

It might not be the prettiest pyramid in Egypt, but it may be the muddiest.

Brightly painted boulders scattered throughout the Sinai Desert.

A massive work of modern art that appears to be a crop circle in the middle of the desert.

Even King Tut was intrigued by the glass of the Great Sand Sea.

An ancient instrument used to measure the waters of the Nile so Egyptian farmers would know whether to expect famine or flood.

Meant to be one of the most extravagant hotels in the world, now an eerie, abandoned architectural gem in Mexico City.

A small window on Via Piella offers a lovely and rare peek at Bologna's lost canals.

A new sculpture calls attention to climate change in the centuries-old city it threatens.

The whole world in one water tank.

A rapidly disappearing glacier filled with extinct grasshoppers, perfectly preserved in the ice.

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

This tree was extinct for a thousand years before sprouting again from a 2,000-year-old seed.

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

This natural wonder drops 16 stories straight down through rare flora and streaming waterfalls.

The closest thing to Mars on Earth.

One man’s vision of living among dinosaurs credits Jesus Christ as the engine of biological evolution.

The Pennsylvania landscape depicted by a quarter mile of mosaics made from used road signs.

"Iron Age" creatures fill this huckster's rusted metal sculpture garden.

The center of the only hemisphere that awards visitors with a commemorative coin.

The easiest way to the highest point in Wyoming is only accessible via one hefty fee.

One of the only spherical 19th century gas containers left today.