Abstract: A next generation very large-scale neutrino observatory must be capable of addressing key open questions and complete our knowledge in neutrino oscillations. Is there CP violation (CPV) in the leptonic sector ? are matter effects in long-baseline oscillations understood and what is the neutrino mass hierarchy (MH) ? The recent measurement of the theta_13 angle of the PMNS mixing matrix has now promoted these open questions as the next milestones, with exciting implications on our understanding of the matter-antimatter asymmetry in the Universe. These challenging physics goals can be uniquely addressed by a new very large underground detector coupled to a long-baseline neutrino beam. Such a new facility will also be an ideal observatory for solar, atmospheric and supernovae neutrinos, as well as for high sensitivity nucleon decay searches. The European neutrino community has early on recognised the importance of this sector and has been strongly supported to prepare the new experiment with the LAGUNA and LAGUNA-LBNO design studies. This consortium is now active in the construction of a large (300t) demonstrator at CERN (WA105). Following the European Strategy Recommendation and the P5 report in the USA, neutrino physics “entered the global era” and the European neutrino community is now exploring the possibility to participate in the ELBNF hosted by Fermilab.
