Futuristic apartment blocks are the backdrop for Montreal surfers hangin' ten on the Habitat '67 standing wave.

Unusual building appears to be haphazardly built from randomly piled bricks.

Ancient rock-hewn town that witnessed key events of Georgian history.

The charmingly disheveled clock tower of Tbilisi's puppet theater.

Mysterious spherical rocks in the semi-desert of western Kazakhstan.

One of the most remote and isolated villages on the Arabian Peninsula.

A Cold War command center is hidden under an idyllic countryside.

The location of the last stand of Charles Manson's doomsday cult.

Second largest wastewater treatment plant in the country.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

Home to the deepest rift anywhere on Earth.

An unrealized dream to wirelessly electrify the entire Earth.

Xul Solar was an artist of alternate worlds, inventor of languages, and dreamer of utopias.

Abandoned castle was once a grand example of Russian privilege, built exclusively to win a frivolous bet between noblemen.

Native Americans built this circle of stones, which was used to predict astronomical events.

Population: 1.