The annual pumpkin flotilla at the Harlem Meer in Central Park. Photo: Central Park Conservancy Pumpkin flotillas, scarefests, haunted cottages—and more spooky things to see and do this week in Harlem and beyond. Halloween on the Harlem Meer Thursday, October 30 4pm-7pm FREE Central Harlem The Charles A. Dana Discovery Center, Central Park, 110th Street between Fifth and Lenox Aves This celebration by the Harlem Meer includes family-friendly crafts, music and entertainment,