The piazza is a basic component of the Italian urban fabric. It is an open exterior space that functions integratively in the city. Connected by streets to other piazzas and other sectors of the city, piazzas create a sense of place and perspective, fitting together like polychromatic pieces of a puzzle to create a total character unique to any specific city section and to the city as a whole (Fig. 1). Although many individual piazzas are closely linked to other nearby piazzas, most piazzas have a primary function. In areas beyond the oldest sections of the cities some piazzas are polyfunctional and resemble small cities unto themselves, as in a small village, where a central piazza serves as a retail, commercial, and governmental node, a center of religious and social activities, and a parking lot (Akinori 1980, 5-7; Webb 1991, 35-65).
Most research on Italian piazzas has focused on the design and development of historically significant ones and on the often monumental, architecture associated with them (Trachtenberg 1988; Benevolo 1991). The focus here is functional: the role of the piazza in the morphology of modern Italian cities. I examine a wide range of piazza types, uses, and functions, and I trace the origins and diffusion of the piazza through the Italian city system from Roman times to the present. Specific emphasis is on the medieval period, 1100-1400, because it is crucial to understanding current piazza location, form, and function. Present-day patterns are summarized in a sixfold typology of piazzas that integrates interactions among location, form, function, and causative process. Data for the study came from a variety of sources: published works; fieldwork in numerous Italian cities, especially Florence between 1991 and 1993; and cartographic resources in the archives of Florence, whose holdings date to A.D. 900.
A piazza is an opening in the city fabric that allows public access and activity in various forms -- walking, riding, driving, shopping, socializing, and playing. The space may be designed or undesigned; it may be only an opening into which street traffic is funneled; it may or may not have landscaped interior spaces for public interaction set apart from the surrounding edges. Essential to this definition and to the analysis in this article are that this space must have a formal name and that it must be recognized as a piazza in public documents such as maps, guidebooks, and civic records. It must be a "conceptual anchor point" in the urban center (Lynch 1960, 102).
History of the Piazza
The notion of the centrally designed space as ritual center, public meeting ground, marketplace, or political center has diffused widely through Western urban morphology since the origin of cities in western Asia (Zucker 1959). The immediate antecedent of present-day Italian piazzas is the Roman forum. The exact origins of forums in Roman cities are unknown, but they probably derived their conceptual and design criteria from at least two sources: the Greek agora, and the small quadrangular centers with crossing streets in the Etruscan settlements of northern and central Italy (Sitte 1945, 1-9; Zucker 1959, 46-50; MacKendrick 1983, 28-112; Stambaugh 1988, 243-254).
The forums in the hundreds of urban centers planned and designed by the Romans in Italy and their empire were rectangular public squares set at the center of two main cross streets, the north-south cardo and the east-west decumanus. The forum and the two crossing streets served as the anchors for the development of the Roman grid-pattern town. At the height of the empire the forum of a Roman city served as a symbolic and geographical center and was a highly functional space for the practice of religion, politics, education, commerce, and recreation (Zucker 1959, 45-62; Stambaugh 1988, 243-286).
In Italy after the fifth century A.D. the decline and disintegration of the empire brought about the retrenchment of the Roman city system and the disintegration of the rationally ordered towns. …