From 23 to 25 September 2025, the CASTIEL 2 All-Hands Meeting (AHM) took place in Tallinn, Estonia. It brought together representatives of the National Competence Centres (NCCs), Centres of Excellence (CoEs), EuroCC2 & EuroCC4SEE, and CASTIEL 2, as well as members of the Project management team. During the conference, the participants discussed achievements, challenges, and shaped the future of collaboration in the field of High-Performance Computing (HPC) in Europe.

The three-day final conference of CASTIEL 2, EuroCC 2, EuroCC4SEE, and the CoEs in Tallinn combined strategic updates, poster sessions, and collaborative workshops. The first day focused on project overviews, visibility initiatives such as the “HPC in Europe” portal and service hub, as well as training surveys and the first NCC & CoE poster session. At the end of the day, a task force meeting was held to discuss key performance indicators and reporting for the third phase of the EuroCC project. On the second day, discussions addressed sustainability beyond EuroHPC JU funding, industry and training working groups, as well as interactive sessions on communication and collaboration. A second poster session also took place. In the afternoon, a workshop was held on improving communication within project teams. During the final day of the event, participants discussed EuroCC 3 and CASTIEL 3, collaboration with the EuroHPC Virtual Training Academy (EVITA), and the meeting concluded with results, networking, and closing reflections.

The gathering marked the conclusion of several key initiatives, including CASTIEL 2, EuroCC 2, and EuroCC4SEE, while also discussing opportunities for future collaboration beyond this stage of the projects. One of the central themes was enhancing the visibility of HPC across Europe to make the technology more accessible to industry, academia, and public administration.