
Coal Mine Tunnels and historical mining sites anchor this landscape south of the growing city, revealing the industrial roots of Contra Costa County. Significant former settlements are mapped as sites, including Somersville, Stewartville, and West Hartley, which once served the region's extraction economy. The terrain transitions from the developed northern corridor along the Southern Pacific tracks to the deep valleys and ridges of the south. Critical water infrastructure, notably the Mokelumne River Aqueduct and Contra Costa Canal, cuts across the hills to supply the thirsty San Francisco Bay area. To the south, the map preserves the rural character of Morgan Territory, showing the Morgan Territory Sch (Site) and the sprawling County Jail Farm along the banks of Marsh Creek. Local transit and land use are defined by historic routes like Empire Mine Road and the recreation areas at Contra Loma Regional Park.
50 named features on this map. Tap any name to fly to it.
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9 editions found
58 maps found

1896 Mt. Diablo
Contra Costa County, CA

1898 Mt. Diablo
Contra Costa County, CA

1911 Byron Hot Springs
Contra Costa County, CA

1913 Woodward Island
Contra Costa County, CA

1916 Byron Hot Springs
Contra Costa County, CA

1916 Lone Tree Valley
Contra Costa County, CA

1943 Mt. Diablo
Contra Costa County, CA

1947 Briones Valley
Contra Costa County, CA

1947 Las Trampas Ridge
Contra Costa County, CA

1949 Briones Valley
Contra Costa County, CA

1949 Las Trampas Ridge
Contra Costa County, CA

1949 Mare Island
Contra Costa County, CA

1951 Mare Island
Contra Costa County, CA

1951 Port Chicago
Contra Costa County, CA

1952 Woodward Island
Contra Costa County, CA

1953 Antioch South
Contra Costa County, CA

1953 Byron Hot Springs
Contra Costa County, CA

1953 Tassajara
Contra Costa County, CA

1959 Briones Valley
Contra Costa County, CA

1959 Las Trampas Ridge
Contra Costa County, CA

1959 Mare Island
Contra Costa County, CA

1968 Port Chicago
Contra Costa County, CA

1978 Woodward Island
Contra Costa County, CA

1991 Tassajara
Contra Costa County, CA

1993 Briones Valley
Contra Costa County, CA

1993 Las Trampas Ridge
Contra Costa County, CA

1995 Briones Valley
Contra Costa County, CA

1995 Las Trampas Ridge
Contra Costa County, CA

1996 Tassajara
Contra Costa County, CA
2012 Antioch South
Contra Costa County, CA
2012 Briones Valley
Contra Costa County, CA
2012 Byron Hot Springs
Contra Costa County, CA
2012 Las Trampas Ridge
Contra Costa County, CA
2012 Mare Island
Contra Costa County, CA
2012 Tassajara
Contra Costa County, CA
2012 Woodward Island
Contra Costa County, CA
2015 Antioch South
Contra Costa County, CA
2015 Briones Valley
Contra Costa County, CA
2015 Byron Hot Springs
Contra Costa County, CA
2015 Las Trampas Ridge
Contra Costa County, CA
2015 Mare Island
Contra Costa County, CA
2015 Tassajara
Contra Costa County, CA
2015 Woodward Island
Contra Costa County, CA
2018 Antioch South
Contra Costa County, CA
2018 Briones Valley
Contra Costa County, CA
2018 Byron Hot Springs
Contra Costa County, CA
2018 Las Trampas Ridge
Contra Costa County, CA
2018 Mare Island
Contra Costa County, CA
2018 Tassajara
Contra Costa County, CA
2018 Woodward Island
Contra Costa County, CA
2021 Antioch South
Contra Costa County, CA

2021 Briones Valley
Contra Costa County, CA

2021 Byron Hot Springs
Contra Costa County, CA

2021 Las Trampas Ridge
Contra Costa County, CA

2021 Mare Island
Contra Costa County, CA

2021 Tassajara
Contra Costa County, CA

2021 Woodward Island
Contra Costa County, CA

2023 Antioch South
Contra Costa County, CA