We all know the major architectural landmarks of New York City?but every day, we pass by big-name architects' lesser-known works and other buildings somehow missing from the guidebooks. Here now, a guide to NYC's under-the-radar architecture in plain sight. The map of 24 sites is designed as a walking tour, so they're in Gramercy and points south. Got nominations for a future map in another 'hood? Head to the tipline. In the meantime, happy archi-gazing!