Dyed by iron oxide over centuries, these sandstone rocks rise thousands of feet into the sky.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

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

A sculpture of the famous photograph stands on San Diego's "Greatest Generation Walk."

Haunting and beautiful trees, doomed to die.

This rare example of a "tidefall" is a spectacular drop from the cliffs down onto the beach.

Concrete strongholds stand guard over the Golden Gate.

A living time capsule of the 1960s Richardson Bay water-front.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Once the largest windmill outside of Holland, with enormous 114 foot sails.

The key to turning shifting dunes into the green oasis of Golden Gate Park.

Tenacious mummies survived dental problems, eternal entombment, and more than their fair share of devastating fires.

A winding path built in secret on the edge of the continent.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

Perfect your fly fishing technique on their practice ponds.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

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

Golden Gate Park's historic collection of plants.

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

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

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

San Francisco's newly reopened hands-on science museum.

The rustic cabin-like decor of this Arts and Crafts-style church reflects the love of nature central to its little-known theology.