Completed in 1999, it has become Fermilab's "particle switchyard" in that it can route protons to any of the experiments installed along the beam lines after accelerating them to 120 GeV. Until 2011, the Main Injector provided protons to the antiproton ring [circumference 6283 meters ] and the Tevatron for further acceleration but now provides the last push before the particles reach the beam line experiments.