There are 39 US Post Offices in Indiana County serving a total of 92,855 residents equating to 2,381 residents per post office. It's estimated that approximately 148,207 packages are handled across the 39 county post offices annually. Indiana County is a county located in the U.S. state of Pennsylvania. As of the 2010 census, the population was 88,880. Its county seat is Indiana. The county was created on March 30, 1803, from parts of Westmoreland and Clearfield counties and later organized in 1806. Indiana County (Indiana meaning \"land of the Indians\") derives its name from the Iroquois Six Nations so-called Indiana Grant of 1768. The area of the Indiana Grant formed a proposed colony bordered on the north and west by the Ohio River, and was made up of what is now parts of eastern Kentucky, northern West Virginia, and western Pennsylvania. The proposed colony or part thereof was variously labelled on maps of the late 1700s as Indiana, Vandalia, Pittsylvania, or Westsylvania. This area was unrelated to and physically separated from the later named (1800), farther west Indiana Territory which became the State of Indiana. Indiana County comprises the Indiana, PA Micropolitan Statistical Area, which is also included in the Pittsburgh-New Castle-Weirton, PA-OH-WV Combined Statistical Area. It is in the defined region of the Pittsburgh media market. Indiana County is served by three different area codes: 724, 814, and 582. The county proclaims itself the \"Christmas Tree Capital of the World\", shipping over one million trees annually."