Thirteen trees representing the original thirteen colonies were planted with soil from historic Revolutionary battlefields.

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

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

The giant pair of sexy legs sticking out the window of this costume store have become its main draw.

This turn of the century masterpiece has a mysterious goaty interloper.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

This private residence was the template for one of the most beloved television homes of all time.

A 300-ship graveyard, with a few still visible at low tide.

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.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

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

A psychedelic labyrinth on the San Francisco bay.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

A huge musical instrument played by the ocean.

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

A mysterious spirit totem at the edge of Navajo lands.

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

Don't blink or you'll miss it.

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

A regular looking rock with an unbelievable history.

One of the most unusual geological features, recognizable from a dozen hit movies.

This old mining town, deep in the California desert, has a year-round population of one.