Urban settlements have always been attractive for the population throughout the history for a better living purposes, working opportunities or even good places for robbery during the wars or migrations. Depending on natural conditions, history or migratory events, cities around the world had known a spectacular evolution over the time, knowing different stages of organized or chaotic growth of their form. Regardless of the population increase registered in the past or the present demographic decline which affects most of the European states, the main cities continued to extend their area. This research presents, in a comparative study, the evolution of three European capitals (Bucharest, Paris and Madrid) in different moments of the history, starting with the 15th century. The study also includes an analysis of the demographic evolution. Using old cartographic resources, recent satellite images and open access databases, the authors analyse the evolution of the form and main directions of urban extension of the three European capitals in relation to the natural conditions and main roads. All data and cartographic resources had been processed and represented using open-source GIS software.