2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/4913I discuss recent advances being made in the physics and astrophysics of cosmic rays and cosmic gamma-rays at the highest observed energies as well as the related physics and astrophysics of very high energy cosmic neutrinos. I also discuss the connections between these topics.Text of Lectures for the D. Chalonge International School of Astrophysics - 9th Course of Astrofundamental Physics, Palermo, Sept. 2002, Revised section on constraints on violation of Lorentz invariance, 50 pagesAstrophysicsHigh Energy Physics - Phenomenologytext