Beyond Southeast Asia’s gateway cities, important determinants of urbanisation can be
identified: the differing strengths of staples-created urban spread effects; geographically-
determined economic realities such easy access to the sea; railway configurations influenced by
geography and economics; and government policy that lay behind infrastructure development.
These factors were the principal determinants of where, and which, cities grew, and whether
small cites grew fast enough to promote the spread of urbanisation and a greater rank-size
regularity of urban systems.