October in NYC is much more than costumes and carved pumpkins. It’s a time for celebrations of architecture, thanks to a month of Archtober events and the Open House New York weekend, which allow you to go behind the scenes at city landmarks. It’s a big sports season, as four of the City’s pro teams (the Knicks, Nets, Rangers and Islanders) begin play. Must-see art exhibitions delve into the mystical worlds of Harry Potter and Frankenstein and the social significance of Charles White’s work. And yes, those interested in spooky stuff can find it at the Bronx’s Boo at the Zoo, the Queens County Farm Museum’s fall programming and the Village Halloween Parade. For details on these and many other happenings, read on.