Gold Rush ship-turned-hotel buried underneath San Francisco's financial district.

San Francisco's oldest operating hotel, with a Victorian atmosphere and a "haunted" fourth floor.

A man-made island in scenic San Francisco Bay.

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

The miraculous hydrant that saved the Mission District in 1906.

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

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

An overlooked and unassuming engineering marvel.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

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

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

A historic hotel that made a cameo in Hitchcock's classic film has no intention of letting guests forget its fame.

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

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.

Big gun installations, built over a massive cemetery, now abandoned & hidden in trees.

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

An essential stop before plundering, BYO Cutlass.

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

A shop full of natural curiosities, carnivorous plants, and costumed taxidermied mice.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

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

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

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