The Indian Head Rock originated as part of “Quaternary Pleistocene and Recent Landslide deposits” from the Kentucky hillside facing the city of Portsmouth. The landslide deposits consist of “unconsolidated angular boulders and finer debris; found at base of steep slopes along Ohio River.”
An early account of the Indian Head Rock (1891) stated that “The rock is not of the freestone formation of the river bed at this point, but is a hard sandstone, and must have rolled from the top of the hill in remote ages. The face was probably made to commemorate the lowest water ever known in the Ohio river since white men settled upon it.” At that time there was already “a multitude of…names and characters, evidently quite ancient” carved in the rock.
The angular surfaces of the boulder were worn smooth over time by the flow of the river. A 1908 newspaper account stated: “That the rock rolled off the hill at some remote period seems assured, as it is of the same formation as the summit of the river hills. It is now smooth as a bowling ball, made so by the motion of the water for generations. Histories of the river of as early a date as 1811 mention its presence.”