Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

This lovely, if imposing, piece of Canadian gothic is possibly the most photographed hotel in the world.

The chiseled jaw of this forgotten American hero still stands tall in a small Indiana town.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

At the base of the Golden Gate Bridge, a small sign basically begs for a high-five.

A monumental cross hides in the trees in Golden Gate Park.

Guns that have been defending San Francisco since 1904.

Recovered from the brink of extinction, at home in the Financial District.

A man-made island in scenic San Francisco Bay.

A walk down memory lane in the heart of one of San Francisco's most notorious neighborhoods.

A speck of nature and art in one of San Francisco’s most notorious neighborhoods.

The grand, column-fronted, sculpture-adorned home of the ambitious digital library.

Half of a house.

A promotional sun clock on the site of San Francisco's great raceway.

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

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

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

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

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

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

Golden Gate Park's historic collection of plants.

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

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.