The project “The City for (E)U” was aimed at young people between 21 and 26 years old, with the aim of involving 28 in the first mobility and 28 in the second, coming from four different countries: Italy, Greece, Portugal, North Macedonia. The aim was to address and discuss the theme of cities, in particular from the point of view of their environmental and social sustainability. This theme was chosen because the generation to which the young people involved belong is one of the first to be forced to deal with a more uncertain future than previous generations, as regards these issues. Through the implementation of the activities during the two mobilities, the first in Turin, Italy, and the second in Athens, Greece, the project “The City for (E)U” achieved first of all the main objective of providing young participants with the opportunity to discover and rediscover through thematic reading lenses - biodiversity protection, waste management, cultural aspect, urban architecture and road system - their own urban contexts and those of the two cities in which the mobilities took place, sharing common practices and strategies in the educational path towards planning the cities of tomorrow. The young participants developed 360° citizenship skills that thus laid the foundations for strengthening a generation that has the urgency to act with democratic tools to promote a future, even in their own cities, that is different and sustainable at an environmental and social level. The project declined the macro-theme object of the reflections through the comparison and the activities on the themes of sustainability, accessibility and inclusion of and in modern cities. The work started from the exploration of the concept of “Doughnut City” and from some specific thematic areas and situations in the cities of Turin and Athens, sharing experiences, good practices and alternative solutions to a non-sustainable system. This comparison and exchange of ideas was favored and enriched by the different national experiences of the young people, coming from four European countries culturally similar, but with profound differences at a social and political level: this aspect contributed to strongly strengthening the international perspective of the project. In this sense, the opportunity offered to participants to participate in two mobilities within the same project created a privileged immersion context to promote interculturality and respect for differences and achieve the project objectives. Through the experience of two very different urban contexts, participants discussed the critical issues common to the two cities and, more generally, to the cities of the present, building at the end of the second mobility an output in the form of a “Booklet” with proposals for the creation and co-construction of more sustainable, accessible and inclusive cities of the future. The participation of all the young participants in the construction of the output promoted active and participatory learning, using the non-formal peer-to-peer education approach during both mobilities. The output can be used and spread by participants and by the organizations of the project consortium for the dissemination of the project and for future educational experiences and proposals regarding the themes of the project “The City for (E)U”. The project has thus achieved the objective of positively strengthening European citizenship skills across the implementation of the project and the planned activities.