On the Upper West Side of Manhattan, the natural contour of the island is evident in the valleys at 125th Street, 106th Street, and 96th Street. In the last one of these, Riverside Drive takes a viaduct above 96th Street and an eponymous neighborhood organization remembers the reason why West End Avenue here takes a dip on its way north and then rises again.
Another clue is William Rickaby Miller’s 1869 watercolor on paper titled Strykers Bay. In this painting we see an unnamed brook flowing towards the Hudson River with the Palisades of New Jersey in the background. This obscure stream is today’s West 96th Street.