The postal road map hints at population density, data not readily available from other types of sources. On top of density, it also captures the shape of population distribution within a given region (This claim is not based on any serious research; I am writing this text only for demo).
The European part of Russia with high population density has the highest road density, decreasing to north and east. The density of roads in the Siberian and Far Eastern Federal Districts is the lowest, and many of them are not connected to the federal network. The postal road density corresponds to the severity of cholera casualty.
The configuration of the road network in the European part of the country is star-shaped, inherited from the network of the cart roads of the Russian Empire: all the main roads diverge by rays from Moscow. This topology of the network may have resulted from horizontal links between cities and regions of the country.
