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

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

A huge musical instrument played by the ocean.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

Floating man-made island and upscale restaurant.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

San Francisco's newly reopened hands-on science museum.

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

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

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

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

An essential stop before plundering, BYO Cutlass.

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

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

The oldest burial ground in the city, final resting place of city founders, Ohlone natives and murderers alike.

Furniture tries to escape an abandoned building in San Francisco.

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

The official atomic museum of the United States explores the explosive and productive history of a much maligned energy source.

A burnt-out motel with priceless Native American artwork in the basement, redeveloped into apartments.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

This grave marks the passing of a historic Jane Doe whose identity remains a mystery to this day.