The Cubic Kilometre Neutrino Telescope, or KM3NeT, is a future European research infrastructure that will be located at the bottom of the Mediterranean Sea. It will host the next-generation neutrino telescope in the form of a water Cherenkov detector with an instrumented volume of several cubic kilometres distributed over three locations in the Mediterranean: KM3NeT-Fr (off Toulon, France), KM3NeT-It (off Portopalo di Capo Passero, Sicily, Italy) and KM3NeT-Gr (off Pylos, Peloponnese, Greece). The KM3NeT project continues work done under the ANTARES (telescope built off coast of France), NEMO (planned telescope off coast of Italy) and NESTOR (planned telescope off coast of Greece) neutrino telescope projects.