The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

The unusual patterns in this rock formation result from two distinct modes of weathering.

Odd outsider art installations surround a Gold Rush-era ghost town.

The most magnificent bottle house in a town strangely full of them.

This small town was built around a marble quarry and named after one of the most famous sources of marble in the world.

This black shoreline is made up of exploded lava particles.

This industrial area was the dumping ground for massive amounts of trash, some of which washes up as tiny bits of sea glass.

Centuries-old hoofprints and wagon tracks reveal themselves after a good winter storm.

An abandoned Jazz Age dream home and con man's hideout in Death Valley.

A massive hydrovolcanic explosion left a half-mile wide crater in Death Valley.

This historic iron-working village is now a ghost town so immaculate that it looks as though it was recently built.

A desert ghost town—occupied for only 12 years—was once home to more than 500 silver mines.

A living snapshot of a different time in America is preserved and maintained by a community of volunteers.

This bridge was constructed from the rubble of the infamous Bastille.

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

At this Minnesota state park you can easily wade across the source of the mighty Mississippi.

Experience a charming 1930s version of "infotainment."

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

"the sweltering inhabitants of Charleston and New Orleans, of Madras and Bombay and Calcutta, drink at my well . . . The pure Walden water is mingled with the sacred water of the Ganges."

This legendary urban waterfall creates a dazzling display of rainbows.

These picturesque Hawaiian falls are home to a rare species of fish that uses a special sucker to climb up cliffs.

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.