Instituto Brasileiro de Geografia e Estatística

About the publication - 1972

The study Division of Brazil into Functional Urban Regions is the first edition of the REGIC survey. It was released in 1972 based on questionnaires relative to year 1966. It is worth mentioning that the name Area of Influence of Cities was only adopted after the second edition, in 1987, but the overall nature of the study is the same.

A total 718 centers were identified in the four urban hierarchies, classified as: Level 1 – Heads of Urban Networks, Level 2 – Regional Centers, Level 3 – Sub-Regional Centers and Level 4 – Local Centers. That general classification has subdivisions that amount to a total 10 hierarchies.

The database for the classification was a municipal enquiry filled out by the IBGE branches in 1966. Three steps led to the classification by hierarchical levels of urban centers and to the delimitation of their areas of influence. At the first step, the number of points obtained by each center in each one of the sectors (agricultural flows, distribution of goods and services to the economy and the population) were added to the total. At the second step, a hierarchy was established according to the total flows of each relationship matrix of municipalities. Finally, at the third step, the hierarchy and the subordination of centers were defined by the grouping of matrices according to the dominance of relations with metropolitan cities – nine previously defined Metropolitan areas – and the city of Goiânia, due to their extensive scope of action and its strong relationship with São Paulo and Rio de Janeiro.

It is worth highlighting this work is the consolidation of a sequence of studies inaugurated with the publication Preliminary sketch of the division of Brazil into homogenous spaces and polarized spaces, of 1967, and the chapter "Centrality" of the publication Subsidies to Regionalization, of 1968 - which made use of the same database as the questionnaires of 1967.