The beach, a public space at the interface between land and sea, is heavily used for tourism and leisure practices, especially during the summer. This attraction generates intensive use of the space and local authorities require data to improve management of their local beaches. In this context, we have analysed beaches as tourism and leisure practice areas to understand their organizations and functioning. This work, based on a study of the Pertuis Charentais beaches on the French Atlantic coast, makes it possible to identify those elements which influence the filling dynamics of these spaces. This approach formalizes a model to facilitate beach management. To demonstrate the model building process, this presentation is organized into three parts. Firstly, we study beach attendance forms to understand the role of accessibility and physical constraints. Secondly, we discuss the filling process in its territoriality and its spatiotemporal dynamics. Thirdly, we study the beachgoers' preferences and their environmental perception. We show how the spatial behaviours of beachgoers are determined by residence status, practices, and environmental sensitivity. These observations are used to calibrate the filling model that is presented in its conceptual dimension.