An architect's childhood fantasy treehouse made real.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

A beautiful geyser under environmental threat.

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

A 6-mile-long lake created by an apocalyptic seismic event and the deadly chain reaction that ensued.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

When it was built in 1929, this historic bridge was the only place to cross the Colorado River for 600 miles.

A geological mystery on Camelback Mountain.

Every year, festive decorations appear on this juniper tree located in the median strip of a busy highway.

A phenomenal assembly of pueblos in New Mexico is the most complete example of ancient ruins north of the border.

Giant origami sculptures tucked into desert scenery beckon passers-by to explore further.

This sparsely populated town offers a look back in time.

A little slice of Florida face-in-a-hole kitsch, unexpectedly located in a small New Mexico town.

This sculpture perfectly models the molecular structure of a drug that was never produced.

This giant pocket watch is the third iteration of a local landmark that has been standing just off the Santa Fe Plaza for over 100 years.

The oldest continuously occupied public building in the United States.

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

This innocuous New Mexico storefront was once the secret jump-off spot for Manhattan Project scientists.

A small side chapel in Santa Fe's basilica is home to the oldest statute of the Virgin Mary in North America.

This cultural center showcases what may be the oldest ongoing community in all of North America.

Deadly airliner crash preserved for those willing to climb and pay respects.

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

Thousands of pieces of art have been carved into the rock at the site of an ancient volcanic eruption.

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.