From March 13–14, 2025, the OSTrails consortium convened in Athens for its inaugural General Assembly, marking a pivotal transition from infrastructure development to widespread adoption. The event gathered over 65 in-person participants, complemented by numerous online attendees, including researchers, infrastructure managers, funders, developers, policymakers, and technical experts. This diverse assembly facilitated in-depth discussions on the current state and future evolution of Open Science within the European Open Science Cloud (EOSC).