At the heart of the LHC are 1,232 dipole magnets, of which this is a cross section. The dipole magnet creates a nearly linear magnetic field that steers the beam of ionized particles around the accelerator. Two beams travel separately in opposite directions through the left and right central channels.
The CMS experiment is one of two geared for a variety of tasks, including finding the elusive Higgs boson. Because the LHC is underground, equipment such as this massive end cap for the CMS experiment must be lowered with cranes. This cap was at one end of the cylindrical detector.
The LHC's primary control center is used to monitor and run the particle accelerator. This pod of screens is matched by four others for other tasks. Separate control centers are used for the experiments. The green screens toward the left signal that all is well with hundreds of subsystems.
This shot shows the exposed innards of a junction between two superconducting magnet sections at the LHC. The electrical bus connection toward the upper right failed in September 2008, overheating and causing a serious operational incident.
The LHC, which fits into the underground tunnel used by an earlier accelerator at CERN, is 27 kilometers in circumference. For scale, the Geneva airport is at the far end of the circle in this shot and the Alps are in the distance.