Linear Accelerator 4 (Linac 4) ME.63 ⋅ Explore ⋅ Meyrin Find out about the 86-metre-long linear accelerator that is scheduled to become the source of proton beams for the LHC from 2020, replacing the 37-metre-long Linear Accelerator 2 (Linac 2). Minimum age Recommended age 12 12