The Large Hadron Collider (LHC) is the largest and most complex machine ever constructed, so it can be hard to fully appreciate its scale.
Consisting of seven experiments — ATLAS, CMS, ALICE, TOTEM, LHCb, LHCf and MoEDAL — these underground nodes around the 27 kilometer (17 mile) long ring of superconducting magnets form the backbone of the physics coming out of the LHC.
Source: Discovery.com