Walter Christaller

Walter Christaller (21 April 1893 – 9 March 1969) was a German geographer whose principal contribution to the discipline is central place theory, first published in 1933. This groundbreaking theory was the foundation of the study of cities as systems of cities, rather than simple hierarchies or single entities. He was primarily concerned with the urban space and worked on the role of towns as geographic-economic units, besides analyzing the relationships between towns of the same region. Provided by Wikipedia