" During the trail years, reaching Independence Rock aroused a kind of collective, Paleolithic carving gene, a powerful urge among the pioneers to leave behind some evidence of their arrival. While the wagon trains rested for a day or two at the rock, the pioneers found it irresistible to scramble up the curved walls and chisel in the hard granite their names or initials, the year, and their hometowns. There is no way of knowing exactly how many pioneers left their initials or names behind on Independence Rock because erosion by wind and water over the past century has removed thousands of these inscriptions. "

― Rinker Buck , The Oregon Trail: A New American Journey