Mount Monadnock

Mount Monadnock is an isolated peak of ancient schist and quartzite in southwestern New Hampshire, rising about 970 meters and standing nearly a thousand feet above any other summit within thirty miles, a prominence that gave the Abenaki-derived word monadnock its modern geological meaning of an isolated hill left standing after the erosion of the softer rock around it. The mountain's rock, part of the Devonian-age Littleton Formation and older Silurian bedrock beneath it, was folded into an overturned syncline by the compressional forces of the Acadian mountain-building event hundreds of millions of years ago, and its bare upper slopes were later scoured by repeated glaciation and, in the nineteenth century, by fires set to clear pasture that stripped away its former forest cover.