A brooding mansion of clinker brick stands out among the Victorian houses of Pacific Heights.

Radioactivity still cause for concern at this urban explorer's paradise.

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

A man-made island in scenic San Francisco Bay.

Alleyway plaque commemorating the death of a fictional character in The Maltese Falcon, not far from the author's home.

Nuclear waste dump site now an environmental sanctuary.

Golden Gate Park's historic collection of plants.

The stones that traveled from Spain to eventually become a holy place for San Francisco's nature worshippers.

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

A still functioning vaudeville carousel that has operated for over a century boasts a colorful menagerie and past.

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

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

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

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

Olfactory delights in San Francisco's Botanical Gardens.

Get lost in this haunting fairytale art walk through a man-made eucalyptus grove.

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

A 140-year-old castle with underground caves hidden in San Francisco.

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

An artsy hidden staircase leads to breathtaking views of San Francisco.

Historic funicular railway, believed to be the shortest railroad in the world.

The mysterious, untimely death of a Canned Heat band member still haunts this unfinished home.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

An unfortunate geological resemblance to Satan has labeled this Pasadena gorge as a passage to the underworld.