Switzerland

From Live Science, June 4, 2018: The Higgs boson appeared again at the world’s largest atom smasher — this time, alongside a top quark and an antitop quark, the heaviest known fundamental particles.

The ProtoDUNE detector is being assembled at the European laboratory CERN. Photo: Maximilien Brice, CERN

The ProtoDUNE detectors for the Deep Underground Neutrino Experiment are behemoths in their own right.