The sign announces the Scottish village's cosmic connections, as it's twinned with Glenelg, Mars.

Edinburgh's oldest statue hides within a parking lot behind the city's iconic cathedral.

Remnants of the 16th-century defensive wall still stand unassumingly within Edinburgh.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

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

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

This boulder stays on its mountain thanks to a huge chain and on the map due to local legend.

An art instillation for the sake of "raising vibrations."

A failed utopian experiment for British expats in the American South is now a Victorian village frozen in time.

North Carolina's finest examples of Native American pictographs have survived for 5,000 years.

This high point in the Great Smoky Mountains is said to be home to the chief of all bears.

A historic dam made famous for its turbines and feature in a Hollywood classic.

This winding road of 318 curves is a must-visit for (careful) motorcycle and sports car enthusiasts.

One of the Cemestos prefab homes built to secretly house thousands of Manhattan Project workers.

The secret city built by the Manhattan Project.

Mile-long cave system near Great Smoky Mountains.

In one of America’s oldest mountain ranges, a long-awaited section of a scenic highway is now open to the public.

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.