To follow up on the turntables still existing on Long Island, besides Morris Park (operable) and Oyster Bay (not operable), there are two others.
1)Greenport, which has been inoperable since the early 1970's.
2) Riverhead, at the Railroad Museum of Long Island. This one, however, is not a former Pennsy turntable. One originally existed in Riverhead and a new bridge was purchased by the museum as part of their site plan. It is not yet installed and is a former Grand Trunk & Western.
Jay