Prairie Grove is a city in Washington County, Arkansas, United States. The population was 2,540 at the 2000 census. It is part of the Fayetteville–Springdale–Rogers, AR-MO Metropolitan Statistical Area. Located here is the Prairie Grove Battlefield State Park. The park spans a large amount of land and contains a visitor center, museum, several monuments, a driving tour and a collection of period buildings and homes you can tour.