There are 20 US Post Offices in Cobb County serving a total of 809,449 residents equating to 40,472 residents per post office. It's estimated that approximately 1,291,971 packages are handled across the 20 county post offices annually. Cobb County is a suburban county located in the U.S. state of Georgia. As of the 2015, the population was 741,334, making it the fourth-most populous county in Georgia. Its county seat and largest city is Marietta. Cobb, along with several adjoining counties, was created on December 3, 1832, by the Georgia General Assembly from the huge Cherokee \"county\" territory\u2014land northwest of the Chattahoochee River which the state confiscated 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 United States 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 the city limits of Atlanta. Its Cumberland District, an edge city, encompasses over 24,000,000 square feet (2,200,000 m2) of office space. The U.S. Census Bureau ranks Cobb County as the most-educated in the state of Georgia and 12th among all counties in the United States. It has ranked among the top 100 wealthiest counties in the United States."