where is alameda county
Alameda County, California. Alameda County (/ËÃ¦lÉËmiËdÉ/ AL-É-MEE-dÉ) is a county in the state of California in the United States. As of the 2010 census, the population was 1,510,271, making it the 7th-most populous county in the state. Its county seat is Oakland.