
The northern edge of the Mt Diablo Base Line meets the expanding industrial and residential fringes of Antioch in this mid-century survey. Heavy industry is concentrated along the Southern Pacific Railroad, evidenced by a massive Filtration Plant and extensive clusters of Oil Tanks. Southward, the landscape shifts into the cattle-and-canyon country of the Morgan Territory. Here, several vanished mining and ranching settlements are preserved as sites, including Somersville, Stewartville, and West Hartley, the latter noted for its Coal Mine Tunnels. The terrain is deeply carved by water and infrastructure, from natural landmarks like Markley Canyon to the massive Mokelume River Aqueduct and Contra Costa Canal. Notable social markers of the era include the County Jail Farm and the Morgan Territory Sch (Aband), reflecting a shift in rural education and land use during the 1950s and 1960s.
50 named features on this map. Tap any name to fly to it.
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9 editions found
1896 · Mt. Diablo
USGS Topo · 1:62,500
1898 · Mt. Diablo
USGS Topo · 1:62,500
1907 · Antioch
USGS Topo · 1:62,500
1908 · Antioch
USGS Topo · 1:62,500
1910 · Jersey
USGS Topo · 1:31,680
1911 · Byron Hot Springs
USGS Topo · 1:31,680
1914 · Brentwood
USGS Topo · 1:31,680
1916 · Lone Tree Valley
USGS Topo · 1:31,680
1916 · Byron Hot Springs
USGS Topo · 1:31,680
1916 · Byron
USGS Topo · 1:62,500