This work analyses the current configuration of the Santander metropolitan area, taking as a starting point the functional urban area recognised according to European criteria. To this end, GIS analysis methods are applied and revealing sources such as Copernicus cover, Global Human Settlement buildings and grid population and statistical sources on residential and daily mobility are integrated. This approach makes it possible not only to analyse the internal organisation of the functional area, but also to quantify in sustainability key the main processes involved: artificial, dispersed, discontinuity and demographic growth in more occupied areas with lower density. The results make it possible to highlight geographical land take and mobility studies in functional urban areas, while allowing for a reflection on the role of the metropolitan scale in the context of the Urban Agenda. We are facing the challenge of urban sustainability and the preservation of green infrastructure that guarantees quality of life in the face of trend urban sprawl, fragmenting and highly soil-consuming. Finally, the usefulness of the aforementioned sources – and their availability to the various European countries – would make it possible to analyse the metropolitan issue with a similar approach in other Spanish and, where appropriate, European systems.