Urban sprawl has become a remarkable characteristic of urban development worldwide in the last decades. However, trajectories and rhythms of sprawl may vary in important ways according to specific geographical and historical characteristics, and these differences need to be contrasted with specific case studies especially for the booming urbanization of the Global South. The purpose of this paper is to study urban growth in the city of Yazd, Iran. Urban growth and other land uses were calculated through treated satellite images for four periods: 1975, 1987, 2000 and 2009. Results reveal that from 1975 to 2009, the urbanized area increased from 1843ha to 13,802ha; that is a rate close to three times the population growth observed for the same period. The Yazd case is interesting for several reasons: first, it is a case of very fast urban growth even for a developing country; second, it illustrates how the fastest rates of urban sprawl may correspond to middle size cities rather than large centers. Third, it portrays a land substitution process in which agricultural land is not the primary provider of urban land which is relatively rare in urban contexts, and fourth, it also illustrate how sprawl may also hide important internal land uses such as the presence of agricultural plots within urban boundaries.