There is a clear relationship between the population growth, population
density, growth of the urban areas and the processes of Sprawl. As urban Sprawl
does, the urban growth also usually leads to an expansive enlargement of the urban
areas. The essential difference is that the general growth of the city is the reason for
the increase in the density of occupation, while Sprawl is characterized by
decreasing density. Therefore, for this study is particularly important to investigate
two of the major factors related to the processes of growth and / or Sprawl in Sofia,
Belgrade and Rome: first, the growth of the urban area and second, the changes in
the density of habitation.