In 1984, the Committee of the World Heritage of the United Nations Organization for Education, Science and Culture (UNESCO), declared to the city of Cartagena de Indias, its historical centre and fortifications as Historical Heritage of Humanity under the denomination of "Port, Fortress and Monumental Set of Cartagena". Due to the importance of the fortifications of the city of Cartagena de Indias as a universal heritage, its conservation is a priority for the Colombian Institutions. It is for this reason that the Environmental Modeling Research Group of the University of Cartagena has been developing research projects, aimed at assessing the risks to which the walls are exposed due to climate change and the social and economic growth of the city of Cartagena. In this first volume are shown the results of several technical studies aimed at describing the current state of the Walls looking at the deterioration of the stone material that constitute the walls and identify the risks to which the walls would be subjected if ordinary and extraordinary plan of maintenance will not be taken.