San Francisco's oldest surviving monument and meeting place for 1906 survivors.

The oldest burial ground in the city, final resting place of city founders, Ohlone natives and murderers alike.

San Francisco Bay's ghost town.

Visible below the waves are memorials to the city's Gold Rush dead.

The largest drain hole in the world.

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

A nondescript building that's been functioning as a speakeasy for nearly a century and a half.

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

Olfactory delights in San Francisco's Botanical Gardens.

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.

Towering basalt columns, a creation of fire and ice.

Trails through lava-carved tube-caves display sparkling bacteria and a rich history.

A Wild West jailhouse that slid down the mountainside.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

Once the product of an inexplicable gold strike, this ghost town is now home to one man and his love of classic machines.

There's nothing creepier than a cemetery next to a clown motel.

Oh, just a motel on the edge of the desert decorated with thousands of clowns conveniently located next to an abandoned graveyard.

This railroad magnate's 19th century tower is more than a little bit out of place in the Nevada desert.

Officially named the "Loneliest Road in America," this barren stretch of Nevada road offers almost nothing but sky and open fields.

This odd California folly seems like it was almost designed to accumulate urban legends.

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

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

This Big Sur waterfall drops 80 feet directly into the Pacific Ocean, and inspired the hillside house up top.