Abstract

One of the most striking aspects of the "constructed environment" is the extent to which the land upon which cities are built is itself the product of human construction, where the artificial extension of the land into developable sites or districts, both in the physical sense of extending the land mass and through transformative processes effected by re-use or legal artifice, like the introduction of air rights, comes to define and form essential, even core parts of major cities. This is the case for many cities in the United States, despite the seemingly paradoxical belief in the limitless availability of "primeval" land. Accordingly, the reconfiguration of central cities, with special attention to Boston, serves to illustrate the scope of artificial construction. In turn, one of the theoretical notions that may shed light on the economic mechanism thereby entailed is the tension in the valuation of real estate between the actual land rent gradient, often invoked in the microeconomic modeling of the urban economy, and a more speculative potential land rent gradient. Hence, this paper provides a conceptual framework for the structure of urban development, but also draws upon a set of historical examples.