I love this book by Allan Jacobs for its attempt to understand what makes a street, and more specifically a pedestrian street, a memorable and significant place. It presumes that architecture and design has something to do with the success of the street. It provides analyses of dozens of streets around the world using quantitative and qualitative measures, and makes soft, qualitative conclusions about them. It concludes with a set of guidelines for architectural form and urban practices that may make a great street.
Here is a summary of the guidelines.