Karns City, PA
Karns City is a borough in Butler County, Pennsylvania, United States. The population was 244 at the 2000 census.
Karns City is located at 40°59′42″N 79°43′33″W / 40.995048°N 79.725743°W / 40.995048; -79.725743.
According to the United States Census Bureau, the borough has a total area of 0.4 square miles (1.0 km2), all of it land.