Between 1884 and 1992 the U.S. Geological Survey drew 178,000 topographic maps covering the nation; the 1:24,000 scale “topo quads” produced from 1945-1992 divide the entire country into 70-square-mile chunks. Nine of those quads comprise this map of New York City.

It makes a bad tourist map, marking all subway lines with the unhelpful “TRANSIT” and doesn't say which bridges you can walk on. It does tell you the shapes of the forts; these were traced from aerial photos, so if it could be resolved on film + legible to whoever looked at the film through magnified lenses, it was included on a topo quad.