Park Slope is consistently rated a top neighborhood in NYC. I have lived here since 1981 and raised my kids here. As far as describing how it "looks and feels," it is a historic neighborhood of 19th century brownstone and limestone townhouses. Much of it is a designated historic district. As far as "lawns," we do have front gardens, but I would not call them lawns, as the houses are attached, but set back a bit from the street. We have backyards as well. The zip code for Park Slope is 11215. It is a neighborhood within Brooklyn, so when you ask if there is a dominant architecture "throughout the city," Park Slope is not a city, but rather a neighborhood in the borough of Brooklyn, in the city of NYC. Apart from the townhouses, there are rental, co-op and condo buildings as well.
Here a New York Magazine article rating Park Slope as the top neighborhood in NYC: http://nymag.com/realestate/neighborhoods/2010/65374/index1.html
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