Wright-Patterson Air Force Base is located northeast of Dayton, Ohio, and encompasses parts of Greene and Montgomery counties. Wright-Patterson Air Force Base has been a leader in military aviation development from the time of airplane inventors Wilbur and Orville Wright to today's aerospace age. With over 30,000 employees, including military, civilian and contractors, Wright-Patterson is the largest single site employer in the state of Ohio with an economic impact of $4.2 billion per year. The base covers more than 8,000 acres of land (12.5 square miles) and provides operational support for more than 100 associate units located at Wright-Patterson.