Around four hundred fifty million years ago, a chain of volcanic islands shaped like an arch collided with proto North America. The North American plate went under the chain of islands. The islands went on top of the edge of North America creating the Highlands and the Kittatinny Valley which is the Ordovician Martinsburg Shale. Quartz and other sedimentary conglomerate was transported to the inland sea, which was over part of the Martinsburg Shale. A small continent then collided with North America around four hundred million years ago. Geologic pressure resulted, which caused compression and then folding and faulting resulted. The folding ran perpendicular to the directional forces. During folding, intense heat melted silica which cemented the quartz and other stones together. Also the intense heat allowed the rock layers to bend, thus the Kittatinny Mountain was born.