The central component of this project would be a new tunnel with a circumference of approximately 91 km, extending across the Franco-Geneva basin. A possible first step could involve the construction of a circular electron–positron collider, envisioned as a veritable Higgs factory, capable of delivering extremely high-precision measurements and enabling detailed studies of the known particles of the Standard Model.

The FCC Feasibility Study, concluded in 2025, explored the project’s scientific potential, technical implementation, environmental impact, territorial integration and financial aspects. Any future decision regarding its possible realisation would follow further international discussions, governance processes and evaluations involving CERN Member States and international partners.