One of the jewels of the Upper Westside is the Pier off 70th Street in Riverside Park. It is one of the old landings that Conrail used to use to bring groceries on to the island of Manhattan, it is where we got our food. Now it is a beautifull esplanade that juts far out in to the Hudson River with views of both the George Washington Bridge and the southern stretch of the city.
They have great stuff going on and you can find the calender here or here.