Designated a National Historic Landmark, Emerald is one of the largest mounds in North America. Covering eight acres, Emerald Mound measures 770 by 435 feet at the base and is 35 feet high. The mound was built by depositing earth along the sides of a natural hill, thus reshaping it and creating an enormous artificial plateau. Two smaller mounds sit atop the expansive summit platform of the primary mound. The larger of the two, at the west end, measures 190 by 160 feet and is 30 feet high. Several additional smaller mounds were once located along the edges of the primary mound summit, but were destroyed in the 19th century by plowing and erosion. Emerald Mound, built and used during the Mississippian period between 1250 and 1600 A.D.,was a ceremonial center for the local population, which resided in outlying villages and hamlets. Its builders were ancestors of the Natchez Indians. By the late 1600s, the Natchez had abandoned Emerald and established their capital at the Grand Village some 12 miles to the southwest.