Brookhaven, formerly North Atlanta, is a city in the northeastern suburbs of Atlanta that is located in western DeKalb County, Georgia, United St…Brookhaven, formerly North Atlanta, is a city in the northeastern suburbs of Atlanta that is located in western DeKalb County, Georgia, United States, directly northeast of Atlanta. On July 31, 2012, Brookhaven was approved in a referendum to become DeKalb County's 11th city. Incorporation officially took place on December 17, 2012, on which date municipal operations commenced. With a population of around 55,366 as of 2021, it is the largest city in DeKalb County. The new city stretches over 12 square miles.