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Historic Districts and Urban Design

During the past decade, preservation has become a viable force in halting innercity decay. A survey by the Urban Land Institute showed that in 1975, "significant" private-market renovation occurred in 70% of American cities with a population of 250,000, and that 60 separate neighborhoods in 20 of the largest cities were undergoing major revitalization. In addition, the success of such places as Ghirardhelli Square in San Francisco and Quincy Market in Boston inspired the nationwide renovation of old warehouses, factories, wharves, and train stations for commercial use. There is an emerging consensus that historic districts can greatly benefit cities. However a great deal of confusion still exists concerning proper criteria for designating "historic" district and procedures for delineating appropriately sized and shaped urban areas. The National Trust for Historic Preservation published a book A Guide to Delineating Edges of Historic Districts which summarizes standard criteria. Most historic districts are quite small and focus upon concentrations of architectural and historic important landmarks. Edges are defined by obvious and convenient criteria such as topography, land use, major streets, and building type. Geographers are identifying and delineating various types of regions or districts in center city. Studies defining the CBD (Central Business District) and land use changes in the Transition Zone have estabished procedures for identifying functional arrangements and spatial patterns. Other studies, such as "The Industrial Revolution and the Emergence of Boston's Central Business District" have explored such functional arrangements in the distant and recent past. Geography, has a long history of interest in spatial pattern and landscape and their interactions. The establishement of historic districts, because of their popularity and potential impact on city structure, would seem a likely focal point for merging spatial and landscape traditions. To be effective, historic district designation must consider the design of cities as well as the design of buildings.