The objective of this work was to quantify and characterise the change in the model of urbanisation witnessed in urban areas structured by medium-sized cities in Spain, differentiating between the behaviour of the central city and the periphery. This was done using land cover data provided by Corine Land Cover and SIOSE and also population and housing data relating to recent decades. The results obtained allow us to affirm that these are the urban areas that have experienced the greatest relative growth in Spain. This growth has mainly been related to the production of low and medium density residential land associated with the production of single-family housing, particularly located on the urban periphery. Even so, in many of these urban areas, and particularly in those in the interior, the production of land has largely been related to non-residential uses. All of this has resulted in the configuration of complex, extensive urban areas that are more fragmented and less dense.