This map shows the counties that make up the Bay Area, along with its three largest cities, San Francisco, Oakland, and San Jose.
For the purpose of simplicity, this website groups the counties in the following large regions
(click region name for more information):
EAST BAY: Alameda, Contra Costa, and Solono Counties
SOUTH BAY: San Mateo and Santa Clara Counties
NORTH BAY: Marin, Napa, and Sonoma Counties
Northern California and the San Francisco Bay Area
Increasingly this site has focused on gardening and the natural world of the Bay Area and Northern California.
The associated blog is called Tom's Garden: Growing by the Bay. Below are some sample images and links to posts.