Cahokia
The largest remaining feature of Cahokia is Monk's Mound. Monks Mound is a massive platform mound with four terraces, 10 stories tall, it is the largest man-made earthen mound north of Mexico. It is 100 ft (30 m) high, 951 ft (290 m) long, 836 ft (255 m) wide and covers 13.8 acres (5.6 ha). It contains about 814,000 cubic yards (622,000 m3) of earth. All of that earth was moved by human power. A 1 bushel basket holds 1.25 cubic feet or 35 liters. If one person could carry a basketful of dirt holding 1.25 cubic feet, then Monk's Mound represents 17,650,863 baskets full of dirt. For comparison, the Great Pyramid of Giza, is a square 230.3m at the base,146.6m tall, and contains 2,583,283m3 of material.