Synchrotron ring tunnel at the point (straight section, 74) where the fast ejected proton beam is taken out for the neutrino beam-line. The proton beam passes through the tunnel wall (top centre) and is directed onto a target, The positive pions and kaons produced in the high energy collisions are converged by magnetic lenses towards the heavy liquid bubble chamber. They decay after a very short time producing the required neutrino beam.