70 years at the high-energy frontier with the CERN accelerator complex

Over the first 70 years of its existence, CERN has created an impressive portfolio of accelerators, many of which are still in operation today. The ‘jewel in the crown’ of the complex is certainly the 27-km tunnel and its infrastructure, built approximately 100 m underground between the Jura mountains and Lake Geneva on the French–Swiss border. In that tunnel, two energy-frontier machines — the Large Electron–Positron Collider and the Large Hadron Collider — have, for the past 35 years, shaped the landscape of high-energy physics. The tunnel could also house future accelerator complexes that have the potential of further defining that landscape for decades to come. CERN marks this year a major anniversary, of 70 years at the forefront of accelerator technology for high-energy physics. The story of its accelerator complex and 27-km tunnel — a major achievement in engineering and physics — is still unfolding.