In the 1940s, Italian architect Mario Cavallè built a dozen of these round homes in northern Milan.

Invented in the mid-19th century, this machine could send copied images via telegraph lines.

South of Bologna, a limestone grotto with a protruding waterfall and a floor full of cave pearls.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

Once a giant oak that served as the region's post office.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

An architect's childhood fantasy treehouse made real.

The preamble to the U.S. Constitution written entirely from vanity license plates hangs in the Smithsonian museum.

Mysterious installations bring levity and light to a sometimes stodgy city.

Where you can hail your favorite fictional commanders-in-chief.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

The brainchild of Eleanor Roosevelt, her "Little Village" was a collectivist dream.

Endless rows of boxes of paper records line the hallways of the archaic federal facility where guns are traced.

This California artist's front yard acts as a gallery for his unique, scrap metal animal sculptures.

This former fire tower is now a rustic observatory that offers amazing views of eagles, hawks, and the Appalachian Mountains.

Take a steam-powered ride straight out of the past on this Appalachian rail line.

This red-eyed chrome beast pays homage to the popular modern myth of West Virginia's insectoid monster.

This remarkable collection devoted to the study of fish includes 1 million preserved specimens from all around the world.

The historic bar where local ship captains, traders, and gold miners would come together to do business a century ago.

Walking by this fence is like strolling along a portal to various fictional worlds.

This dilapidated ship carcass covered in trees is a striking sight.

In this subterranean brick arcade, a small shop continues the ancient practice of bookbinding.

This large Sitka spruce that appears to be floating in mid-air, has defied logic for years.

Where else would a linchpin of post-colonial Native American cuisine anchor the menu but a museum?