Island where motor vehicles are banned -- home to the only carless highway in the United States.

Strange physical sensations and optical contradictions keep visitors coming back for more.

These dramatic cola-colored falls have appeared in a poem by Henry Wadsworth Longfellow and a song by Sufjan Stevens.

"The Most Boring Road in the State."

This lone tree and dramatic sandstone outcropping are so beloved by Michiganders they can be found on one of the state’s coins.

Large one-man sculpture park in Michigan.

A monument to the art of slicing people open.

A display of magnificent stained glass windows is the first exhibit of its kind.

Each of these gorgeous, intricately decorated rooms is painstakingly crafted to the scale of 1 inch: 1 foot.

The oldest continuously occupied public building in the United States.

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.

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

More than 7,000 gallons of water pour over these cascading red quartzite waterfalls every second.

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.

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

This ghost town was once a cult-like religious utopian settlement.

Oddly shaped rock formation, misassociated with a nearby utopian community.

One of the world’s largest collections of petroglyphs records 2,000 years of human activity.

The fifth-longest natural arch in the world, and the longest outside China.

See massive fossils that are over 200 million years old in northeastern Arizona.

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.