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Mapping the Bay

Introduction to Mapping the Bay: Exhibit & Student Mapmaking Contest

The maps in this online exhibit include highlights from the Earth Science & Map Library's Historic Maps of the Bay Area Collection, supplemented with additional historic and modern maps. They are organized loosely by region (Bay Area as a whole, East Bay, North Bay, Peninsula, San Francisco and South Bay) and by theme. You will also see several different types of maps—nautical, topographic, geologic, road maps, census maps and more.

What is the Bay Area?


"no other U.S. city-region is as definitionally challenged [as the Bay Area]"– Richard Walker, professor emeritus of geography at University of California, Berkeley

The geographic definition of the San Francisco Bay Area can vary widely depending on the person you ask. The region's topography and unusual commute patterns caused by the presence of three central cities and employment centers located in various suburban locales have generated unique development patterns. This unusual landscape of development has contributed to considerable disagreement between local and federal definitions of the area.Since World War II, a nine-county definition for the Bay Area has taken hold, including the counties that directly border the San Francisco, San Pablo, and Suisun estuaries: Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Solano, and Sonoma counties.


This map shows the five subregions of the Bay Area which are generally divided along county lines.

Student Mapmaking Contest

The exhibit also coincides with our first student mapmaking contest. The contest invited Bay Area students to take part in the long tradition of Mapping the Bay using their own creativity, imagination and sense of what makes this region home. As this exhibit (launching in May 2020) comes at a time when many of us are confined to a much smaller slice of the Bay Area than we normally see, we hope these maps, both new and old, inspire you to see the Bay Area in a new light.

Exhibit curated by Bonita Dyess, Heiko Muhr, Erica Newcome, Susan Powell, and Sam Teplitzky, staff members at the Earth Sciences & Map Library.