For most New Yorkers, simply escaping the city is a primary summer goal. But to get the quickest and easiest change of scenery, make a beeline for the rooftop bars and backyard gardens that burst into life once the mercury hits 75. Since they're not exactly in plain view, we’ve rounded up the most impressive newcomers—along with mainstays you simply shouldn't miss—to kick off a season full of happy hours. These are not mere white-wine-and-sunshine joints; these bars serve serious cocktails from big-name mixologists.