Portions of the abandoned, partially submerged, approximately 100 year old 69th Street Transfer Bridge wharf and pier in New York City. When active, freight cars were offloaded onto to waiting barges via the bridge. The remnants have been left to provide an underwater habitat. The structure is located in the Hudson River, just off the West-Side Highway, between 69th and 70th Streets.
This provides a bit more context for the overall site.