The Harling Site is a prehistoric Caddo Indian ceremonial site on the Red River north of Honey Grove in Fannin County. Its principal feature, a rectangular flat-topped mound measuring seventy meters (230 feet) north-south, fifty-two meters (170 feet) east-west, and two meters (7 feet) high, was destroyed by agricultural operations in 1963. The University of Texas carried out a brief archeological investigation of the site in 1960. Shell tempering in some of the pottery fragments indicates that Harling is related to certain Caddo sites in the Arkansas River drainage of Oklahoma such as Spiro and Harlan, and possibly to McCurtain Phase sites farther down the Red River. It is later than the Sanders Phase component at the Sanders Site, which is not far downstream from Harling. The construction date of the mound falls somewhere between A.D. 1000 and 1300, probably in the later part of that span. In post-Indian times the mound was used by unknown persons, possibly slaves, as a cemetery.
The Harling mound was the westernmost instance of a flat-topped rectangular mound of general Mississippian type. As an outpost at the western fringe of the Caddoan archeological area, on the frontier between the Indian farmers of the southeastern woodlands and the hunters of the plains, the mound could have been a ceremonial reflection of prosperity resulting from the trade that very likely went on between these two kinds of people, as appears to have been the case at other frontier sites, such as the George C. Davis Site in Cherokee County. There are signs of Indian villages, where such trading would have gone on, in that part of the Red River valley, but none of them has been specifically related to the mound itself. The records and specimens are curated at the Texas Archeological Research Laboratory of the University of Texas at Austin.