Neutrino telescopes have become essential tools at the intersection of astrophysics and particle physics. Originally conceived to provide insights into some of the most energetic and distant phenomena in the Universe, these large-scale detectors will also contribute to the precision measurement of the oscillation parameters.
This seminar will begin with an overview of current and planned neutrino telescopes, highlighting their complementarity in location, design, and physics goals for multi-messenger astronomy. Therefore, the focus will turn to KM3NeT, which uncharted the PeV territory with the detection of the most energetic neutrino ever observed so far, and its ability to probe atmospheric neutrinos to reveal some of the remaining unknowns in neutrino physics, such as their mass ordering. Special attention will be given to KM3NeT/ORCA and its contribution to validating the three-neutrino flavor paradigm while testing the non-unitarity of the neutrino mixing matrix. The resolution of this open question remains one of the most exciting, as it allows the exploration of new physics scenarios beyond the Standard Model.