Open Mike touched on it above--counties are the seat of the courts in the U.S. Federal, state, and county courts-at-law, and the Justice of the Peace, etc. are all in the county courthouses. Here in Texas with something like 250 counties, it pays to know the names of the counties in your region of the state because the National Weather Service (thus the local weather folks) generally present risky situations (thunder storms, flash flooding, tornado watches or warnings) by county. Living here you need to know that Jacksboro County, Palo Pinto County, and Erath County are northwest/west/southwest of Tarrant County (where Fort Worth and many other small cities are) because our weather usually comes from the Northwest or the Southwest, depending on what is driving the storms, cold air from the Northwest or wet air from over Mexico.

SRS