There are 23 US Post Offices in Lancaster County serving a total of 187,475 residents equating to 8,151 residents per post office. It's estimated that approximately 299,231 packages are handled across the 23 county post offices annually. Lancaster County is a county located in the U.S. state of Nebraska. As of the 2010 census, the population was 285,407, making it the second-most populous county in Nebraska. Its county seat is Lincoln, the state capital. The county was created in 1859, and the original county seat was the village of Lancaster. Lancaster County is part of the Lincoln, NE Metropolitan Statistical Area. In the Nebraska license plate system, Lancaster County was represented by the prefix 2 (it had the second-largest number of vehicles registered in the state when the license plate system was established in 1922). In 2002, the state discontinued the 1922 system in Lancaster, Douglas and Sarpy counties."