THE CASTRO VALLEY LAND BRIEF
Land in the
East Bay Hills/Western Diablo Range setting.
Castro Valley CDP has 16.8 square miles of land in Alameda County. Its Census reference point is in East Bay Hills/Western Diablo Range, within Central California Foothills and Coastal Mountains.
Oak woodland, chaparral and grassland occupy foothills and low coastal mountains around the Central Valley. Narrow agricultural valleys interrupt this landscape of dry summers and wetter winters.
Regional context: Central California Foothills and Coastal Mountains ↗ · Classification at the Census reference point
Castro Valley and Alameda County
Castro Valley is associated with Alameda County in the Census boundary data. Start with the parcel’s tax bill to match the property to that jurisdiction, then confirm which government handles its land use.
Castro Valley by land and water
The Census records 0.22 square miles of water within Castro Valley, or 1.3% of its total area. It is 8.9 percentage points lower than the 10.2% recorded for Alameda County. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Castro Valley CDP has 5.7 times the land area of nearby Fairview CDP (2.97 square miles). These areas describe boundaries, not comparable property prices.

