There are 13 US Post Offices in Clinton County serving a total of 37,114 residents equating to 2,855 residents per post office. It's estimated that approximately 59,238 packages are handled across the 13 county post offices annually. Clinton County is a county located in the U.S. state of Pennsylvania. As of the 2010 census, the population was 39,238. Its county seat is Lock Haven. The county was created on June 21, 1839, from parts of Centre and Lycoming Counties. Its name is in honor of the seventh Governor of New York State, DeWitt Clinton, however some sources suggest the namesake is Henry Clinton. Clinton County comprises the Lock Haven, PA Micropolitan Statistical Area, which is also included in the Williamsport-Lock Haven, PA Combined Statistical Area."