The Large Hadron Particle Collider

Massive Magnet
The central piece of the CMS detector weighs over 1900 tons. In this photo, taken in February of 2007, the central magnet is shown just after it was lowered into its place. According to CERN's website, this was a "challenging feat of engineering, as there are just 20 cm (8.6 inches) of leeway between the detector and the walls of the shaft."

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