  == Northern Border ==  Using the boundary definitions included in both the current Park Slope and Prospect Heights articles, the triangle bounded by Flatbush to the north, Park Place to the South, and 4th Avenue to the west would thus be part of no Brooklyn neighborhood whatsoever. My view is that the present northern border is actually Flatbush Avenue, not Park Place.  Though historically this area may not been part of Park Slope, and was also not part of the Park Slope historical district, Flatbush is now commonly understood to be the boundary between Propsect Heights to the North and Park Slope to the south. As evidence, the official NYC website shows the northern boundary at Flatbush avenue. I'd submit that this is a higher quality source of neighborhood boundaries than New York Magazine.  