The increasing importance, in the international debate on Universities, of the so-called "Shanghai ranking" encouraged us to look at it more closely, to analyse how it works, and to transfer its results to a world map, in order to reveal the geography of world universities, its points of concentration (three three megalopolis) and its weak points (the rest of the world, save a few exceptions). In reaction to the insufficiencies and skews of this classification, other rankings have been devised, three of them are also analysed and mapped.