Smith Creek is an excellent example of a Coles Creek ceremonial site and the only one of its kind on the driving trail. The site includes three earthen mounds surrounding a large central plaza. Professional archaeologists have determined that Smith Creek was occupied from ca. AD 750 to 1350 and that the mounds were constructed beginning around AD 1000 or perhaps a little earlier.
Mound A, adjacent to Highway 24, is the site's largest monument, at over 30 feet in height. Originally shaped like a truncated pyramid, its eastern corner was removed in 1960 when the state highway was built. Its location on the bluff edge adds considerably to its illusion of great height when viewed from the west. Archaeologists conducting excavations in 2013 and 2015 found that the mound was constructed in multiple stages. They also found evidence of buildings as well as pottery, stone, and bone artifacts associated with the mound summits.
East of the highway, Mound B is located at the northern perimeter of the site. Mound B is a rectangular platform mound surrounded by a ditch or moat, a feature that is not uncommon on ceremonial sites dating to this time. A wide causeway connects the mound with the plaza to the south. Mound C, southeast of Mound B, is currently eroding into Smith Creek. Its original dimensions are unknown. 2013 and 2015 excavations found that Mound C is similar to Mound A in that it was built in multiple stages and had evidence for buildings and related activities associated with mound summits.
Significantly, archaeologists also determined that the plaza at Smith Creek is man-made. Consisting of artifact-rich fill that ranges from 1.5 to 3 feet deep, the plaza was constructed beginning as early as AD 750-850 and probably predates the mounds. The mound-and-plaza site configuration seen at Smith Creek is a signature of the Coles Creek Period (ca. AD 750-1200) and archaeologists believe it served as a model for later Plaquemine Period (ca. AD 1200-1600) site plans. In fact, the plaza construction at Smith Creek spans the Coles Creek-Plaquemine transition, as portions of the plaza continue to be filled in until about AD 1350. Coles Creek people had also begun to experiment with agriculture, planting and harvesting a number of native domesticates in addition to hunting, fishing, and foraging for wild plant foods. This innovation eventually led to the more intensive, corn-based agriculture of the Plaquemine culture. Corn was found in Plaquemine Period contexts at Smith Creek but not in earlier Coles Creek ones.