There are 4 US Post Offices in Brewster County serving a total of 9,179 residents equating to 2,295 residents per post office. It's estimated that approximately 14,651 packages are handled across the 4 county post offices annually. Brewster County is a county located in the western part of the U.S. state of Texas. As of the 2010 census, the population was 9,232. Its county seat and only city is Alpine. The county is named for Colonel Henry Percy Brewster, a Secretary of War for the Republic of Texas. Brewster County is the largest county by area in the state, over three times the size of the state of Delaware, and more than 500 square miles (1,300 km2) bigger than Connecticut. It is one of the nine counties that comprise the Trans-Pecos region of West Texas, and borders Mexico. Oilman, geologist, and historian Clayton Wheat Williams, Sr., operated a ranch near Alpine in Brewster County, though his residence was in Fort Stockton."