Contra Costa County, California

Contra Costa County, California ni msumba uchoko panji nkhalwe (county pachingelezi) iyo ikusangika mu boma likulu la California mu charu cha United States of America. Boma likulu la California lina tumisumba 58 mukwati mwake (counties).

Contra Costa County, California
Maboma/makomboni (counties) gha California