LEP tunnel completed
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The excavation of the tunnel for the Large Electron–Positron Collider – Europe’s largest civil-engineering project prior to the Channel Tunnel – was completed on 8 February 1988. The two ends of the 27-kilometre ring came together with just one centimetre of error. The picture above shows a tunneling crew after completing a section of the tunnel between points 2 and 3 on the LEP ring.