James River Fall Line

James River Fall Line. The Unique Geography That Made Richmond. , Richmond was settled where the Piedmont and Coastal Plain regions of Virginia meet on the James River. The Fall Line is the point where boats could no longer proceed upstream due [SIC] the rapids formed by the change in elevation. The elevation drops around 120 feet over the course of seven miles., The rapids are formed by water tumbling over hard granite rocks. This is part of the 900 miles Atlantic Seaboard Fall Line, which stretches from New York to Georgia. Here, water flowing from the Appalachians makes its final descent to lower tidal estuaries. These igneous rocks formed over 330 million years ago when North America and Africa collided in the formation of Pangea., In Virginia, the Fall Line has impacted the settlement of many of our major cities. Alexandria, Fredericksburg, and Petersburg all sit on the same Fall Line. To the west, the Piedmont Region is marked by hard bedrock. To the east, the Atlantic Coastal Plain is characterized by softer soils, the result of over 150 million years of erosion of the mounts that once stood here.