The LHC is preparing to restart at almost double the collision energy of its previous run. The new energy will allow physicists to check previously untestable theories, and explore new frontiers in particle physics. When the LHC is on, counter-rotating beams of particles will be made to collide at four interaction points 100 metres underground, around which sit the huge detectors ALICE, ATLAS, CMS and LHCb. In the video above, engineers and technicians prepare these four detectors to receive the

The Large Hadron Collider is one of the largest machines in the world. Its purpose is to fire subatomic particles at each other so we can better see how they function. Find out more about this massive machines in Colossal Machines, on Thursdays at 8pm, on National Geographic UK. | National Geographic UK