Abstract Throughout the history of mankind, ports have been the hub of coastal towns and the changes undergone there have reflected the town's historical, social and economical evolution. Nevertheless, building and adapting them implies a constant battle between technology and the forces of nature, requiring the application and development of the most advanced techniques in the construction process. Taking this into account, it seems paradoxical that, despite their indisputable cultural, historical and technical value, in cities port constructions that compose the seafronts of our cities are forgotten cultural heritage. These assets required technical, human and economic resources for their construction far superior to those necessary for building their surroundings, as is shown in the case study, and are a true reflection of the inheritance of past generations, helping us to understand a town's history and identity. For this reason, it is thought necessary to claim the right to the heritage of these constructions and contribute to the study of underwater cultural heritage in ports, so that this may be a basis for appraising and conserving it where necessary. In order to achieve this, it is fundamental to establish which aspects it is necessary to know in these building works. It is especially of interest to know what building systems were used and how they were put into practice, not forgetting the materials used in the construction process. This article has been written with the aim of bringing the latter to light.