The ancient hieroglyphics and etchings at Big Rock Shelter, located in northern Henderson County, have held the interest of amateur and professional archeologists for many years. Big Rock is the only known rockshelter in the Caddoan area of East Texas. Because the shelter has protected the archeological deposits, materials such as floral and faunal remains have been well preserved. Excavations by archeologists from Southern Methodist University indicate that the shelter was first occupied about a.d. 600 by prehistoric Indians. The designs carved into the surface of the shelter were made, at least in part, by these people. Later, prehistoric Caddo Indians occupied the shelter.
The site is located on a high ridge that forms the divide among the Trinity, Neches, and Sabine rivers. The shelter overlooks a vast area of hickory and oak uplands that is transitional from the East Texas pine forests to the prairies. The sand hills of the ridge are the site of permanent springs that supplied water for the occupants of the shelter.
The shelter was most likely never a permanent residence but a place for occasional overnight stays that may have had religious significance. It opens to the north and therefore provides poor protection from winter weather. However, during the rest of the year it forms a cool, protected location.
Petroglyphs were carved on both the ceiling and back wall of the rockshelter and to the east of the shelter's drip line. The carvings are of two general categories, representations of animal footprints and clusters of abstract geometrical designs; the latter consist of both rectilinear and curvilinear motifs. The recognizable animal prints, all of which occur outside the shelter, are deer, turkey, and raccoon.
Faunal remains from the shelter indicate that the Caddoan occupants made use of deer, rabbits, turtles, and mussels, the latter two from the permanent springs located only a few hundred feet away. Remains of hickory nuts were also found. Stone tools found at the site were made of pebbles probably brought in from the gravel deposits on the Trinity and Sabine rivers. The most common arrowheads were Scallorn and Alba points. The few prehistoric ceramic fragments recovered in the Caddoan deposits seem to be representative of the Saunders Focus, a prehistoric Caddoan unit.