Although it markets itself as a beer garden, Birreria is actually a restaurant. Almost all of the space is filled with tables reserved for those eating food. That is not to say, however, that there is nothing in it for a rooftop drinker. For a start, the beer is produced right there on the rooftop using a combination of Italian and American beermaking methods. There are also views of both the Flatiron and Empire State buildings -- although the bulky retractable roof unfortunately gets in the way and somewhat diminishes the feeling of being outdoors. The main drawbacks are those of Eataly in general. It is expensive (expect to pay $10 for a beer) and so popular that in good weather you'll have to arrive early or arrive late to avoid an unbearably long line.