more at scitech.quickfound.net Public domain film from the National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. en.wikipedia.org The John Heinz National Wildlife Refuge at Tinicum is a 1000 acre (0.8 km2) National Wildlife Refuge spanning Philadelphia and Delaware counties in Pennsylvania. Located in Tinicum Township, the refuge is adjacent to the Philadelphia International Airport. Established in 1972 as the Tinicum National Environmental Center, it was renamed in 1991 after the late H. John Heinz III who had helped preserve Tinicum Marsh. The refuge serves to protect the largest remaining freshwater tidal marsh in Pennsylvania; approximately 350 acres (0.8 km2). When land acquisition is complete, the refuge will consist of 1200 acres (4.9 km2) of varied habitats... The history of Tinicum Marsh, the largest remaining freshwater tidal wetland in Pennsylvania, goes back to 1634 and the region's first settlements. Dutch, Swedish and English settlers diked and drained parts of the marsh for grazing. At that time, the vast tidal marshes stretched over 5700 acres (23 km2). Rapid urbanization since World War I has reduced tidal marshes to approximately 200 acres (0.8 km2). The remnant of this once vast tidal marsh is protected by the refuge. A diked, non-tidal area of 145 acres (0.6 km2), adjacent to the eastern end of Tinicum marsh, was donated by the Gulf Oil Corporation to the City of <b>...</b>