“Thalassanté, traces of water-weaved co-existences” is an attempt to document the building of Thalassanté, a self-managed and collectively constructed space by the sea in the port of Marseille. Within it, it houses collaborative projects whose actions are related to social solidarity, ecological transition, symbiotic relations and the sea. It is a place for sharing knowledge and co-creating, made possible by the people that spend time there together. Above all, it’s hoping to give to the people of the neighborhood a place to co-exist and allow the practices that take place within it to constantly redefine its identity. Through its documentation and analysis, elements that are producing qualitive common space, open to all city’s bodies, can be identified. The results of this research inflict the rethinking of the methods of space production and hopefully enrich the architectural design tools by observing everyday practices that emerge spontaneously from the interaction of its users. The documentation started while being in Marseille on an Erasmus program. This body of work was produced at UTH by Papaioannou Styliani-Ligeia and supervised by Iris Lykourioti.