Archeological information provided by the Missouri Department of Natural Resources:
The main source for information about the early Indian daily life is in the ground. Like pages of a book, archaeology can reveal stories about who the people were and how they lived.
Information is revealed not only by the artifact but also by its relationship to other things. For example, finding a single projectile point gives an archaeologist a certain amount of information. But its presence among projectile points and chert waste in a small area tells archaeologists that the site was a hunting camp. On the other hand, dense debris and evidence of houses indicate a village. Past soil disturbances can be detected and reveal where post holes, hearths, roasting pits, and storage pits have been dug.
A grid system controls the archaeological site horizontally and defines the excavation squares. The white stakes in the cave were part of the grid from past excavations. Vertical wall cuts, called profiles, allow the archaeologist to view a cross section of the many cultural strata that make up then deposits and are still visible in the cave. The flat surfaces are horizontal profiles, produced as the excavation proceeded from the most recent to the earliest (deepest) cultural levels. A mapping station, the three wooden stakes near the fence, were used for recording depths in the cave deposits.
As archaeologists dig, they destroy the part of the site they are excavating. But archaeologists record as much information as possible as they dig and keep careful records of what they have found. Without these records, the stories of the past would be destroyed forever.
Preliminary survey work started in 1949, and excavations in the Cave began in 1952. Between 1950 and 1955, the University of Missouri and The Missouri Archaeological Society conducted extensive excavations with astonishing results; Artifacts found in Graham Cave, associated with charcoal, dated by the radiocarbon method, provided important evidence about man's adaptation to the environment at the end of the ice age. The uncovered deposits revealed evidence of human life dating back about ten thousand years. This established the date of human habitation in the Midwest more than five thousand years earlier than previously thought. The lowest layers contained artifacts of the Archaic Period (10,000 to 8,000 B.C.) of the Dalton Period (8,000 to 7,000 B.C.) while artifacts from the Woodland Occupation (800 A.D.) lay on top levels.
The cave's placement in 1961 on the National Register of Historic Places - the first archaeological site in the United States to be designated in this way - recognized its significance to the prehistoric period of the central United States. In 1961, Frances Graham Darnell donated the cave and the surrounding 237 acres to the state to be preserved as a park. Although the interior remains closed to protect the remaining deposits from artifact hunters, the interior is in full view, interpretive signs provide visitors with historical and archaeological information and point out interesting discoveries.