San Francisco Bay, one of the finest natural harbors
in the world, covers some 450 square miles. It is two hundred feet
deep at some points, but about two-thirds is less than twelve feet
deep.
The bay region, the only real break in the coastal
mountains, is the ancestral homeland of the Ohlone and Coast Miwok
Indians.
It became the gateway for newcomers heading to the state's interior
in the nineteenth and twentieth centuries. Tourism today is San
Francisco's leading industry.