Bullitt County is a countyin the U.S. stateof Kentuckylocated in the far western Bluegrassregion known as the Knobs, with an area of 300 square miles and a population estimated at 75,653 in 2009. Just south of the city of Louisville, part of the Louisville metropolitan area commonly known as Kentuckiana, the county is home to several commuter towns including the cities of Hillview, Lebanon Junction, Mount Washington and Shepherdsville - the county seat. The western fifth of the county (40,000 acres) is reserved for military training as part of the United States Army post of Fort Knox.