Sullivan County, Pennsylvania, United States, is divided into 13 incorporated municipalities. State law defines the two kinds of municipalities present in the county: four boroughs and nine townships. In the 2010 census, the population of Sullivan County was 6,428, making it an "Eighth Class County", defined by Pennsylvania law as "having a population of less than 20,000 inhabitants". Its county seat is Laporte, which was the smallest county seat in Pennsylvania by population, as of 2001.
