FROM EASTON AND WYOMING TO THE GENESEE CASTLE: TERRAIN AND MILITARY GEOLOGY ALONG THE ROUTE OF “SULLIVAN’S MARCH” (1779), PENNSYLVANIA AND NEW YORK
Sullivans main army followed Indian trails in making a physiographic transect from the Great Valley to the Genesee Riveracross Blue Mountain, the Pocono Plateau, the Lackawanna basin, and the glaciated Allegheny Plateau. The route made use of such landscape features as the Wind Gap, the North Branch Susquehanna River valley, and the east side of Seneca Lake. Another brigade under Brig.-General James Clinton followed the North Branch on the Allegheny Plateau from Lake Otsego, NY, to a junction with Sullivan at Tioga Point (Athens), PA. The campaign journals provide descriptions of the terrain traversed by both forces and of many individual geologic features observed en route, e.g., waterfalls (Spring Falls near Pittston, PA, Buttermilk Falls at Falls, PA, and those at Watkins Glen, NY), the western Finger Lakes (from Seneca to Conesus), and the monolithic Standing Stone on the North Branch south of Towanda, PA.
Terrain and geologic conditions had a major impact on the Battle of Newtown, fought on the banks of the Chemung River south of Elmira. In achieving victory, the American forces routed the enemy from a strong defensive position behind an esker and a swamp, bounded by the river on the west and a steep mountain spur on the east.
Though the military significance of Sullivans campaign is a matter of argument, its social and economic importance is beyond dispute. It depopulated a large tract of Indian country just beyond the frontier and introduced a host of land-hungry Americans to the rich bottomlands of the upper North Branch Susquehanna, the Chemung, and the Genesee. The soldiers journal entries undoubtedly reflect the verbal reports to families and neighbors that spurred a post-war influx of settlers into the former Iroquoian homeland.