Patrick shows Mound 4 to the west of Mound 3 but to the south of Cahokia Creek. Present contours suggest the mound is approximately 38 meters (124.7 feet) by 34 meters (111.5 feet). The base of the mound is 128 meters above sea level (419 .9 feet above sea level) and its highest point is 128.6 meters (421.9 feet), giving a height of 0.6 meters (2.0 feet).
Previous descriptions of Mound 4 have suggested it was much higher. Thomas (1894) gives a height of 8 feet (2.4 meters). The Patrick Map shows it as a small, round mound comparable in size to Mound 1 and located directly north of Mound 25 and east of Mound 5, south of Canteen Creek. The mound is hard to detect in early aerial photographs, and no early USGS maps show it. The UVVM Map shows a northward extension of the 128-meter contour line in the area where Mound 4 should be, which suggests the mound was obliterated by modern construction. Moorehead makes brief mention of Mound 4 (Moorehead 1929). However, there are no published reports of excavations in it.