Spatial integration, in general, is related to spatial-diffusion processes without barrier effects-that is, without geographical discontinuities between contiguous areas that would indicate regional gaps. Since this article examines the postal structure not as an institution but as a representation of social integration, its primary focus is on location (the geographical distribution of the various offices) rather than administration (the technical and bureaucratic side of the postal delivery system). Therefore, the main sources of information are density maps, which depict the total number of post offices in a particular area. The analysis is based upon the assumption that proximity to a dense web of communication routes correlates with better integration and that discontinuities correlate with state disconnection. Granovetter, for example, claimed that clustered social ties within a region produce a "local cohesion" that leads to national fragmentation. Density maps of postal systems reveal potential fragmentations and threats to state unity. Nevertheless, since these maps do not depict how people actually used the postal system, they can display only the apparent unavailability of communication, not that definite communication occurred. Therefore, they are mainly useful for disproving state integration; the contrary would require additional proof.