The hawari of Cairo - narrow non-straight alleyways - are the basic urban units that have formed the medieval city since its foundation back in 969 AD. Until early in the C20th, they made up the primary urban divisions of the city and were residential in nature. Contemporary hawari, by contrast, are increasingly dominated by commercial and industrial activity. This medieval urban maze of extremely short, broken, zigzag streets and dead ends are defensible territories, powerful institutions, and important social systems. While the hawari have been studied as an exemplar for urban structure of...