This natural marble cave is one of only five national monuments in Oregon.

Coastal dunes, site of buried Egyptian movie set and former utopian colony.

A chain of bells connect the California Missions and honor the legend of the "King’s Highway."

Windswept and remote, this island was once the home of a rare mammoth and today is home to a rare tree.

In the "Danish Capital of America," a replica of one of Copenhagen's most iconic buildings.

Hidden in the Santa Ynez Mountains off Highway 154, this tiny restaurant once served as a stagecoach stop.

California's largest steel arch bridge.

Colorful Native American paintings are hidden within this small cavern.

The restored estate of a wealthy rancher was once at the heart of an unprecedented legal victory.

Pay your respects to departed pets, both celebrity and otherwise.

The stone walls of a home built to withstand a California wildfire still stand after more than a century.

A bomb shelter and some fireplaces are all that remain of the house Fred Roberts tried so hard to keep standing.

The beautiful behemoth is one of the largest trees of its kind in the United States.

The ruins of the movie ranch owned by actor and stuntman Ray "Crash" Corrigan.

From Japan to Italy, this California park explores the world's cultures through their gardens.

An Old West film set seen in countless TV shows and movies is open for the public to explore.

A spiritual center in the Santa Monica Mountains founded by Alice Coltrane after the death of her husband and fellow jazz musician John Coltrane.

French prisoners carved these boats from the bones of their meat rations.

Rusty pieces of metal jutting out of a breakwater are all that's visible of the 12,500-ton ocean liner that capsized just off the beach.

A basement full of treasures lies beneath this inn that has worn many hats throughout its 140+ years.

Graffiti-covered ruins that were once part of a farm owned by a mental hospital.

Centuries of crashing waves carved out this small hole in the rock, which lights up at certain parts of the year.

It's not your typical library, memorial, or book store.

This nonsensical smiling boat shuttles passengers between two places they could've easily walked between.