fulton_county,_georgia | country | united_states <tsp> alpharetta,_georgia | ispartof | georgia_(us_state) <tsp> alpharetta,_georgia | ispartof | fulton_county,_georgia <tsp> fulton_county,_georgia | countyseat | atlanta <sep> fulton county is a county located in the north-central portion of the us state of georgia as of the 2020 united states census, the population was 1,066,710, making it the state's most-populous county and its only one with over one million inhabitants its county seat and largest city is atlanta, the state capital approximately 90% of the city of atlanta is within fulton county; the other 10% lies within dekalb county 
the county of fulton georgia is in atlanta and alpharetta belongs to the county.fulton county georgia atlanta is the state's most populous county