Reilly’s Law, developed in 1931 by William J. Reilly, proposes a method for evaluating the relative influence of two urban centers on a population residing in an intermediate region. Based in particular on Converse’s mathematical formulation from 1949, this approach determines how these urban centers attract residents based on their respective sizes and their distance from the intermediate area. According to this law, the attraction exerted is directly proportional to the size of the urban centers and inversely proportional to the square of their distance from the intermediate area.