An early-20th-century "dacha" village of quaint cottages curiously located in a modern part of Moscow.

Colorado's only true geyser is hidden within the San Juan National Forest.

A 300-yard long natural tunnel runs through a ridge deep in the Appalachian Mountains.

Railroad came. People came. Railroad left. Town died.

Traditional Appalachian dances such as the Georgia Rang Tang and the Shoo-Fly Swing are kept alive at this weekly event.

This North Carolina museum is keeping the pinball craze alive, with a little Space Invaders on the side.

A curious whirlpool formation supposedly capable of entangling or engulfing branches, tree trunks, or whole rafts full of hapless tourists.

The secret city built by the Manhattan Project.

All that's left of the quintessential "cabin in the woods."

Mysterious ancient boulder carved with petroglyphs in the mountains of Western North Carolina.

Wild lights and sound effects turn a walk through some caves into an eye-popping 1960s tourist attraction.

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

Some North Carolina Cherokee have been keeping their history alive for decades with a single play.

Mile-long cave system near Great Smoky Mountains.

Step back in time on this preserved 1800s farm.

This road in the Great Smoky Mountains was supposed to assuage a displaced community, but ended up a $52 million dead end.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

This geothermal hot spring hides beneath a slowly growing mineral dome.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

An ethereal glowing blue ocean cave in Croatia.

Stalactites and stalagmites in a beautifully lit cave.

A serpentine highway twists and turns over the treacherous Norwegian Sea.

A religious-themed park filled with folk art to bring biblical stories to life that fell into disrepair and now being restored.

Rustic natural hot springs in the deciduous rain forest.