A natural dome made of volcanic glass in Inyo National Forest.

Neither Spanish settlers nor anyone since has been able to tell who built these strange California rock walls.

A statue commemorate Tommie Smith and John Carlos's brave protest at the 1968 Olympics, a watershed moment for civil rights.

Housed in a memorial lighthouse, this museum relays the history of surfing, beginning with the antics of royal Hawaiian teenagers.

From working out of his garage to the James Beard semifinals, one Tucson baker has kept his fan base—and his grains—local.

The ghostly remains of an accidental sea.

This stretch of beach along California's central coast is a busy highway for the largest seal in the northern hemisphere.

The second-largest gold nugget in existence, displayed in a Las Vegas casino conveniently named the Golden Nugget.

Las Vegas's very own 40-foot-tall fire-spewing praying mantis.

Fans of vintage Vegas, kitsch, and toy pony-based gambling now flock to a casino called The D.

Nevada's largest cactus collection stands outside a candy mogul's small factory.

The restored and active Victorian-era final resting place of San Francisco.

This incredible collection of vintage pinball machines can be played at 25 cents a pop.

Stepping away from the glitz of mobsters and casinos to learn about the other history of Vegas.

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

San Francisco's first World's Fair, dedicated to the wonders of California.

An elaborate gift from Claus Spreckels is now a piece of San Francisco history.

Golden Gate Park's historic collection of plants.

Olfactory delights in San Francisco's Botanical Gardens.

Guns that have been defending San Francisco since 1904.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

A huge musical instrument played by the ocean.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

Only hotel where you can legally launder money.