Large Hadron Collider (LHC). A prototype section of the LHC under test at CERN, the European centre for particle physics near Geneva. The LHC is due to start operations in 2006-7. It will accelerate counter- rotating beams of protons to an energy of 7 TeV (7000 GeV), and then bring them to collide head on. The LHC will consist of a 27 km long underground ring of superconducting magnets. The magnets will be housed in a pipe-like structure, or cryostat, cooled by liquid helium to keep them at an operating temperature of 1. 9 degrees above absolute zero. The photo, which shows a 106 m long 'test string' of eight magnets, was taken in 2001.