The Large Hadron Collider repurposed an excavation tunnel built for the Large Electron-Positron Collider, which was used until 2000 and whose construction involved the largest civil engineering project in Europe before the Channel Tunnel.

CERN—the European Organization for Nuclear Research—is the world's largest particle physics laboratory, with the Large Hadron Collider serving as its largest tool.

Learn about five of the largest particle accelerators on Earth, which, as of 2026, are led by the Large Hadron Collider at the European Organization for Nuclear Research.

Although built from 1996 to 2008, the Large Hadron Collider relies on accelerators built starting in 1955 to help bring protons to 99.9999991% the speed of light—about 3.28 million football fields per second.

On average, the Large Hadron Collider uses 1.3 terawatt-hours of electricity annually—equivalent to about 124,000 US homes—generated by a French substation.

At the Large Hadron Collider, protons are accelerated so close to the speed of light that they would lag behind a laser by just 10 feet after 14 minutes of travel.

Through 2038, the Large Hadron Collider research program is expected to generate societal benefits of €25.6B, or €3.3B more than operating costs and investments.

The Large Hadron Collider is the world's largest cryogenic system, which uses 10,000 metric tons of liquid nitrogen and 120 metric tons of helium to cool 36,000 metric tons of magnets to temperatures colder than outer space.

The High Luminosity Large Hadron Collider will provide a tenfold increase in particle collisions compared with the initial LHC infrastructure by increasing the number of ions in collision bundles and by concentrating the ion beams.

Watch an animated visualization of how the Large Hadron Collider works, including how particles are accelerated through a series of machines before colliding and how collision data is collected and distributed around the world.

Take a 360-degree tour of ATLAS, one of two general-purpose detectors at the Large Hadron Collider and the largest particle detector by volume ever built. (VR device-compatible)

Weighing about as much as the Eiffel Tower, ATLAS integrates concentric layers of sensors to analyze the properties of particles produced in collisions of accelerated ions. More than 3 petabytes of data—equivalent to 600 years of music—are collected from this experiment each year.

The first circular particle accelerator was narrower than the average cereal bowl

The 1939 Nobel Prize in physics was awarded to Ernest Lawrence for inventing the cyclotron. By comparison, the Large Hadron Collider is 5 miles in diameter and is the largest cryogenic system in the world, cooling its electromagnets to temperatures colder than those found in outer space.

Each year, the Large Hadron Collider undergoes a winter shutdown—when electricity costs are highest—and bringing it back online requires weeks of tests, including some involving high-energy particles from outer space.

Since 2026, the Large Hadron Collider has provided heat to thousands of French homes and businesses through a system that harnesses hot water from the accelerator's cooling circuits.

The novel heat exchanger extracts thermal energy from water heated after it circulated through equipment and transfers it to the town of Ferney-Voltaire's heating network. The system is expected to prevent the release of thousands of tons of carbon dioxide and reduce the atmospheric heating caused by the accelerator's water passing through a cooling tower.

Unlike the other major detectors at the Large Hadron Collider, the Compact Muon Solenoid—one of two general-purpose detectors—was built above ground and then lowered underground in sections for reassembly.

The total length of superconducting wire at the Large Hadron Collider spans about 250,000 kilometers (155,000 miles)—enough to wrap around the equator 6.8 times.

Despite fears of creating black holes, the Large Hadron Collider produces collisions with energies of 13.6 trillion electronvolts, about 10 million times smaller than the energy needed to create the lightest possible black holes.

At the Large Hadron Collider, scientists have transformed lead into gold—a process known as chrysopoeia, which alchemists sought for centuries.

At the CERN Control Center, where the Large Hadron Collider and connected accelerators are managed, champagne bottles from parties commemorating major milestones, such as the first collisions or a new record energy, are collected.

As of 2026, 75 of the 86 particles discovered by the Large Hadron Collider have been found by the LHCb experiment—a detector that explores the decay of particles made of beauty and charm quarks.

Particle accelerators propel matter toward small targets at high speed

Devices like cathode-ray tube televisions were once basic particle accelerators, but modern ones, such as the Large Hadron Collider, use massive magnetic fields and circular tunnels to achieve energies high enough to recreate the conditions just after the big bang.