One of the last remnants of the city's Chinese nightclub scene is now a dive bar selling killer mai tais.

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

The taxidermied remains of the "last wild grizzly bear in California" and of the symbol of the state of California.

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

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.

An overlooked and unassuming engineering marvel.

Golden Gate Park's historic collection of plants.

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

A hidden subterranean installation offers a view of the sky.

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

Nestled in the heart of San Francisco’s bustling Financial District stands a unique homage to the Mayan and Beaux Arts.

The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

A modern mechanical planetary system, part of a 10,000 year clock.

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

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

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.

A psychedelic labyrinth on the San Francisco bay.

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

A huge musical instrument played by the ocean.

Olfactory delights in San Francisco's Botanical Gardens.

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

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