• View of the Golden Gate Bridge, taken from the Marin Headlands, looking across the bay back towards San Francisco, seen in the distance.

    Golden Gate

    National Recreation Area California

Alcatraz - Federal Prision Period

Did You Know?

Basalt pillows

Geologists sometimes call Franciscan pillow basalt “greenstone” because it contains green minerals formed in an interaction between the basalt and hot, mineral-rich seawater.