From the website:
Authentic, expansive, and well preserved, Prairie Grove is known as one of America’s most intact Civil War battlefields. With more than 900 acres, this park commemorates the site of the Battle of Prairie Grove, where on December 7, 1862, Confederate and Union forces clashed in a fierce day of fighting that resulted in 2,700 casualties. This battle marked the last major Civil War engagement in Northwest Arkansas. The park offers walking and driving tours, programs, and weekend events. At the Hindman Hall Museum, artifacts recovered from the battle are displayed.