There are 35 US Post Offices in Chautauqua County serving a total of 174,143 residents equating to 4,976 residents per post office. It's estimated that approximately 277,952 packages are handled across the 35 county post offices annually. Chautauqua County is the westernmost county in the U.S. state of New York. As of the 2010 census, the population was 134,905. Its county seat is Mayville, and its largest city is Jamestown. Its name is believed to be the lone surviving remnant of the Erie language, a tongue lost in the Beaver Wars; its meaning is unknown and a subject of speculation. The county was created in 1808 and later organized in 1811. Chautauqua County comprises the Jamestown-Dunkirk-Fredonia, NY Micropolitan Statistical Area. It is located south of Lake Erie and includes a small portion of the Cattaraugus Reservation of the Seneca."