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

An elaborate gift from Claus Spreckels is now a piece of San Francisco history.

The key to turning shifting dunes into the green oasis of Golden Gate Park.

A man-made island in scenic San Francisco Bay.

Golden Gate Park's historic collection of plants.

This turn of the century masterpiece has a mysterious goaty interloper.

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

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

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

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

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

A nondescript building that's been functioning as a speakeasy for nearly a century and a half.

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

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

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

This Paris art space celebrates the creativity and ingenuity that springs from abject poverty, especially in Africa.

What looks like a normal building is really a hollow facade hiding a subway vent.