List of regions of Serbia
The regions of Serbia include geographical and, to a lesser extent, traditional and historical areas. Geographical regions have no official status, though some of them serve as a basis for the second-level administrative divisions of Serbia, okrugs (districts of Serbia). Not being administratively defined, the boundaries of the regions are in many cases vague: they may overlap, and various geographers and publications may delineate them differently, not just in the sense of regions' extents, but also in the sense as to whether they form separate geographical entities or subsist as parts of other super-regions, etc. For the most part, regions correspond to the valleys or to the watershed-areas of rivers and were simply named after them (some even a millennium ago), while mountain ridges and peaks often mark boundaries. In some cases, a defined region may refer only to the inhabited parts of the valleys (see župa). Valleys and plains along the largest rivers are special cases. The Serbian language usually forms their names with the prefix po- (SavaPosavina, Danube (Dunav)Podunavlje, TisaPotisje, etc.). Considered geographical regions per se, they usually have very elongated shapes and cover large areas (Pomoravlje), sometimes spreading through several countries (Posavina, Potisje, Podrinje, etc.). For the