Extraradio or urban periphery[1]​ are terms from urban geography, specifically from the study of urban structure, with which the urban space located beyond the expansion is designated. A distinction can be established, in which case the periphery is the space furthest from the urban center")[2]​ and the suburbs remain in an intermediate position.

Its characteristics, depending on the specific conditions of each city, determine the intensity of occupation (low in the garden city, high in the collective habitat) and the disposition and greater or lesser presence of different land uses: residential (segregated into different social categories, from prestigious urbanizations to those of the middle classes, working-class neighborhoods or shanty towns), commercial (particularly large surfaces that include leisure areas and massive parking lots), industrial (industrial estate, heavy industry, technology park). or transportation (railway facilities, airports, ports, highways). In a typical radial arrangement, it will include areas of peri-urban space and will connect with the metropolitan area.[3]​.