The only visible piece of San Francisco's most famous shipwreck.

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

A famous alternative culture epicenter and where Joplin serenaded young hippies.

One of few lasting examples of the brief octagon craze that developed into folly.

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

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

Barely visible foundations remain where Stow Lake’s “observatory” once welcomed visitors.

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

Amazing meticulous gardens of personal wood carvings, Hydrangea, Canna, and many other flowers.

Join the circus for a few lessons to learn clowning, acrobatics, and Chinese contortion.

Appropriation-friendly collection of books, periodicals, and more.

San Francisco's most expensive hotel suite includes a secret passageway rumored to have been used by JFK.

A man-made island in scenic San Francisco Bay.

The remains of a 12th-century chapter house in Golden Gate Park.

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

San Franciscans leave gifts and messages for the magical beings that live behind the tiny, mysterious door installed on a tree in Golden Gate Park.

Since 1973, this block has been home to the most concentrated collection of murals in San Francisco.

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

Adolph Sutro's little-known, geographically inaccurate, deprecated monument.

Longtime headquarters of controversial boys' club for the world's wealthiest and most powerful.

The miraculous hydrant that saved the Mission District in 1906.

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

Nuclear waste dump site now an environmental sanctuary.

Golden Gate Park's historic collection of plants.