Pawnee Rock changed very little for ten thousand years, standing as a grass-covered hill with a fifty-foot-high face on the southeast side while wind, water, and vegetation slowly eroded the stone. Its top once was as high as the observation platform on top of the stone shelter, but in the late 1800s the site was quarried for building materials, and trees and a road to the top were added. At the rim of the rock, cannon barrels once rested on two concrete bases. People have enjoyed the vistas from Pawnee Rock for thousands of years, but only recently have people left their mark there, with hundreds carving their names into the sandstone. On July 4, 1846, Susan Magoffin wrote, "I cut my name, among the many hundreds inscribed on the rock and many of whom I knew." Some of these carvings are historic and need to be protected.