Broad Run High School is a public secondary school in Ashburn, an unincorporated area in Loudoun County, Virginia, United States, and is part of the Loudoun County Public Schools system (LCPS). Of the county's ten public high schools, Broad Run (BRHS) has experienced the most change in both its physical and demographic environments during its nearly four decades of existence. Originally a rural school serving all of eastern Loudoun County, the explosive growth of the county's population beginning in the mid-1990s has resulted in systematic reduction of Broad Run's attendance area as it spun off six of the district's high schools from within its original boundaries.
Nicknamed “Cornfield High” when it opened, Broad Run’s facilities, academic and extracurricular environments have always been challenged by its location in one of the fastest growing counties in the United States. Since 1969, the county population has increased nearly seven-fold (most of it in the east), straining education budgets, infrastructure and local politics. For Ashburn, this has resulted in constantly shifting attendance boundaries as new school after new school is opened every year, at all levels, elementary, middle and high.