Reva, South Dakota Reva, South Dakota Reva is an unincorporated community in Harding County, South Dakota, United States. Although not tracked by the Census Bureau, Reva has been assigned the ZIP code of 57651. The community has the name of Reva Bonniwell, the daughter of a first settler. The Battle of Slim Buttes occurred here on September 9–10, 1876, in the Great Sioux Reservation between the United States Army and Miniconjou Sioux during the Great Sioux War of 1876. It marked the first significant victory for the Army since the stunning defeat of General George Custer at the Battle of Little Bighorn in
Battle of the Little Bighorn known today as Custer Hill. At least 28 bodies (the most common number associated with burial witness testimony), including that of scout Mitch Bouyer, were discovered in or near that gulch, their deaths possibly the battle's final actions. Although the marker for Mitch Bouyer has been accounted for as being accurate through archaeological and forensic testing, it is some 65 yards away from Deep Ravine. Other archaeological explorations done in Deep Ravine have found no human remains associated with the battle. According to Indian accounts, about 40 men made a desperate stand around Custer on Custer Hill, delivering volley fire.