  On the strength of a double Nobel prize winning experiment (Super)Kamiokande
and an extremely successful long baseline neutrino programme, the third
generation Water Cherenkov detector, Hyper-Kamiokande, is being developed by an
international collaboration as a leading worldwide experiment based in Japan.
The Hyper-Kamiokande detector will be hosted in the Tochibora mine, about 295
km away from the J-PARC proton accelerator research complex in Tokai, Japan.
The currently existing accelerator will be steadily upgraded to reach a MW beam
by the start of the experiment. A suite of near detectors will be vital to
constrain the beam for neutrino oscillation measurements. A new cavern will be
excavated at the Tochibora mine to host the detector. The experiment will be
the largest underground water Cherenkov detector in the world and will be
instrumented with new technology photosensors, faster and with higher quantum
efficiency than the ones in Super-Kamiokande. The science that will be
developed will be able to shape the future theoretical framework and
generations of experiments. Hyper-Kamiokande will be able to measure with the
highest precision the leptonic CP violation that could explain the baryon
asymmetry in the Universe. The experiment also has a demonstrated excellent
capability to search for proton decay, providing a significant improvement in
discovery sensitivity over current searches for the proton lifetime. The
atmospheric neutrinos will allow to determine the neutrino mass ordering and,
together with the beam, able to precisely test the three-flavour neutrino
oscillation paradigm and search for new phenomena. A strong astrophysical
programme will be carried out at the experiment that will detect supernova
neutrinos and will measure precisely solar neutrino oscillation.
