The Susquehanna River's islands, wetlands, flood plain, and woodlands form unique habitats for rare plant and bird species, but over the centuries human activity has harmed these sensitive areas. This area was once one of the most active centers of trade in southern York County. In 1830, the charcoal iron furnace called York Furnace was built just north of here along Otter Creek, producing pig iron that was carried to markets downriver on canal barges. Within a few decades, a village with a large store, hotel, warehouse, and several wharves developed. Businesses closed after the furnace ceased operations in 1875 and the canal was abandoned in 1894. Nature is now slowly erasing the human imprint at York Furnace, while recent efforts by public agencies, environmental groups, and private interests have worked to improve water quality, restore natural areas, and preserve open spaces throughout the watershed, enhancing the health of both the river and the Chesapeake Bay.