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

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

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

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

This mountaintop beacon is only lit three times a year but shines like some kind of all-seeing eye.

Thousands of crosses and markers for soldiers who lost their lives in Iraq and Afghanistan blanket a California hillside.

Art in the form of a winding, man made crack in stone.

A masterpiece in Golden Gate Park by virtue of the artist’s debt.

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

A huge musical instrument played by the ocean.

The longest burning light bulb in the world.