The LHC circulated first beams on 10 September 2008, discovered the Higgs boson in 2012, and completed three data runs before entering Long Shutdown 3 in July 2026. The High Luminosity LHC era begins with first beams targeted for June 2030 and is planned to run to about 2041.
The Story So Far
- 10 Sep 2008First beams circulate the full 27 kilometre ring. Nine days later, a faulty magnet interconnect causes a helium release that damages a sector and forces fourteen months of repairs.
- Nov 2009Beams return. Within weeks the LHC becomes the highest energy collider in history, passing the Tevatron.
- 2010 to 2013 · Run 1Physics at 7 and then 8 TeV collision energy. The dataset that changes everything.
- 4 Jul 2012ATLAS and CMS announce the discovery of the Higgs boson at about 125 GeV. The 2013 Nobel Prize in Physics follows for Englert and Higgs.
- 2013 to 2015 · LS1Long Shutdown 1. Magnet interconnects consolidated so the machine can reach design energy safely.
- 2015 to 2018 · Run 2Collisions at 13 TeV. ATLAS and CMS each record roughly 140 fb-1, and Higgs couplings to the heaviest known particles are observed one by one.
- 2019 to 2022 · LS2Long Shutdown 2. The injector chain is overhauled: Linac4 replaces the original 1978 linac, and the Booster and PS are upgraded for brighter beams.
- 2022 to 2026 · Run 3Record energy of 13.6 TeV. Extended by a year, Run 3 ultimately delivers more collision data than Runs 1 and 2 combined, ending with the final protons on 27 June 2026.
- Jul 2026 · LS3 beginsWhere we are now. The machine warms up, 1.2 km of accelerator comes out, and the High Luminosity hardware goes in. Four years of the biggest rebuild in the LHC's history.
The Road Ahead
- Mid 2028The injector complex restarts, recommissioning beams two years ahead of the main ring.
- Jun 2030Target for first HL-LHC beams, the moment our countdown tracks. Beam commissioning, then the start of Run 4 physics at 14 TeV.
- 2030 to mid 2030s · Run 4The first High Luminosity run. Levelled luminosity at five times the original design, pileup up to 200, and the fastest accumulation of collision data ever attempted.
- Mid 2030s · LS4A shorter shutdown for maintenance and targeted upgrades, including plans to bring LHCb and ALICE into the high luminosity picture more fully.
- Late 2030s to ~2041 · Run 5+The programme's closing act, pushing the total dataset toward 3,000 fb-1, roughly ten times everything gathered before the upgrade.
The Dataset, Era by Era
Another way to read the same history is through integrated luminosity, the measure of how much collision data each era produced. Run 1 delivered about 30 inverse femtobarns, enough to find the Higgs. Run 2 roughly quintupled that with about 140 per experiment. Run 3 outdid both runs combined and pushed the career total toward 450. The High Luminosity era is planned to take the total to about 3,000, meaning the machine's first eighteen years will end up producing only around 15 percent of its lifetime data. Every long shutdown on this page was the price of one of those multiplications, and LS3 buys the biggest one.
Reading the Pattern
Two things stand out from the timeline. First, the rhythm: run, stop, rebuild, run again, with each pause buying capability that headlines rarely capture. The unglamorous 2019 injector overhaul is a big reason the 2030 machine can be fed bright enough beams at all. Second, the arithmetic of patience: after fourteen years of operation the LHC had collected roughly a third of the data it will ultimately produce. The machine spending 2026 to 2030 in pieces is the same machine whose most productive decade has not started yet.
For what the rebuild actually involves, read the Long Shutdown 3 guide. For what the new era delivers, start with the HL-LHC explained.