Check out a hidden collection of vintage neon signs.

The top of a giant mesa, just outside of Amarillo, appears to float in the sky above.

A sculpture made of 10 Cadillacs as a monument to the “Golden Age” of the American automobile.

This constitutionally sound Muffler Man harkens back to the days these attractions were a must-see.

A time-capsule monument reminding future generations of the importance of efficient and effective use of natural resources.

A spur fit for a giant sits just off Highway 281 in Texas.

A community-funded monument to kindness in the face of life's difficulties.

This former luxury resort in Kaua'i is now an abandoned relic.

Once the site of the Hawaiian monarchy, this building was originally designed as a palace.

The only royal palace on U.S. soil has been a territorial capitol, a military headquarters, and a prison for a queen.

This monument built by Japanese American immigrants spent decades underground.

Now a pedestrian bridge, this was once part of a narrow-gauge railroad that ran along the east coast of Kauai.

The southernmost point in the United States is a beautiful place to look at but a deadly place to wade in.

Babe Ruth and others planted saplings for a 1930s tourism campaign. The saplings grew as the area faded.

This unusual lava tube spouts seawater during high surf.

These ancient sacred grounds granted amnesty to those who managed to reach them.

A priest with no formal artistic training used basic house paint to create gorgeous religious scenes inside this historic church.

A controversial memorial at the place where Captain Cook met his violent end.

Hiding in plane sight.

This saltwater swimming pool, which is the last of its kind in the United States, is slowly crumbling within sight of multiple high-end beachside hotels.

On Waikīkī Beach, a monument to four extraordinary individuals of dual male and female spirits who brought the healing arts from Tahiti to Hawai'i.

Labor provided by Great Depression-era programs restored these 25,000 acres in Tennessee.

An engraved boulder marks the spot where Patsy Cline's life ended in a plane crash.

The former home of the 11th president of the United States.