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

A pair of mutilated bronze octopuses slump at the base of the monument honoring California's admission to the U.S.

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

An acoustic anomaly with a mysterious cause.

This hulking behemoth is actually five interconnected towers built in the 1960s.

The superstar of Cold War nuclear bunkers has been featured in countless films but is now barely operational.

A wood-and-steel sculpture garden featuring an artful interplay of nature and machinery.