CERN Large Hadron Collider

46.2338°N, 6.0532°E.

The CERN Large Hadron Collider on the Franco-Swiss border west of Geneva, Switzerland — the largest scientific instrument ever built, operated by the European Organization for Nuclear Research (CERN). The collider consists of a circular tunnel 27 kilometres in circumference buried 50–175 metres underground, with two beam pipes accelerating proton or heavy-ion beams to 99.9999991 percent of the speed of light in opposite directions and crossing them at four major detector stations (ATLAS, CMS, ALICE, LHCb). Construction began in 1998 and the collider was first activated in September 2008; first proton-proton collisions occurred in March 2010. The 2012 announcement of the discovery of the Higgs boson at the ATLAS and CMS detectors confirmed the last unverified prediction of the Standard Model of particle physics, 48 years after the particle was first proposed by Peter Higgs. The total construction cost was approximately 4.75 billion Swiss francs.

The largest scientific instrument in human history, built across two countries to test predictions about the structure of matter that the theorist who made them lived just long enough to see confirmed.