Cobb County is a suburban county of Atlanta in the U.S. state of Georgia, located in the north central portion of the state. As of 2019, the population was 760,141, making it Georgia's third most-populous county. Its county seat and largest city is Marietta.Along with several adjoining counties, Cobb County was founded on December 3, 1832, by the Georgia General Assembly from the large Cherokee County territory—land northwest of the Chattahoochee River which the state acquired from the Cherokee Nation and redistributed to settlers via lottery, following the passage of the federal Indian Removal Act. The county was named for Thomas Willis Cobb, a U.S. representative and senator from Georgia. It is believed that Marietta was named for his wife, Mary.Cobb County is included in the Atlanta-Sandy Springs-Roswell, GA Metropolitan Statistical Area. It is situated immediately to the northwest of Atlanta's city limits.
Its Cumberland District, an edge city, has over 24 million square feet (2,200,000 m2) of office space. As of 2017, Major League Baseball's Atlanta Braves play in Cumberland.The U.S. Census Bureau ranks Cobb County as the most-educated in the state of Georgia and 12th among all counties in the US. It has ranked among the top 100 highest-income counties in the United States. In October 2017, Cobb was ranked as the "Least Obese County in Georgia".