what county is alphretta
(678) 297-6001. Alpharetta, located in Fulton County, was incorporated December 11, 1858. Years ago, Alpharetta was the county seat of the former Milton County. In 1932, Milton County merged into Fulton County.The city's name is a variation of a fictional Indian girl, Alfarata, in a 19th century song, The Blue Juniata.678) 297-6001. Alpharetta, located in Fulton County, was incorporated December 11, 1858. Years ago, Alpharetta was the county seat of the former Milton County. In 1932, Milton County merged into Fulton County.