Sidewalks are not just spaces that should be designed with safety in mind, Jacobs argues, they are safety-creating devices. Cities, unlike towns and suburbs, are literally full of strangers. However, sidewalks, when operating well, create an environment that makes you or me feel safe sharing the street with the city's strangers.
Jacobs speaks quite approvingly of Boston's very own North End neighborhood, writing that its streets are some of the safest one could ever experience (and the North End was quite different in her day). Its sidewalks work so well because they are populated at all times throughout the day. People in the North End use the sidewalks before, during, and after the work day; they use them for pleasure strolls, performing errands, socializing, and going out for a meal, a drink, or a pastry. The North End is what planners call a mixed-use neighborhood—many activities perform there, all in close contact. As a result, there are almost always what Jacobs calls “eyes on the street.”
A place like the North End rarely needs closed-circuit television monitoring or doormen to watch the street. Instead, through its day-and-night activity, the North End has built-in eyes—the activity all along its sidewalks.