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.

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.

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.

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.

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.

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.

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.

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.

The Worldwide LHC Computing Grid—a distributed system of 2 billion gigabytes of storage across over 40 countries—manages data produced by the Large Hadron Collider.

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

Although built from 1996 to 2008, the Large Hadron Collider relies on accelerators built starting in 1954 to help bring protons to 99.9999991% the speed of light—about 2.73 million football fields per second.

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.

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)

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.

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 6.2 times.

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.

At CERN's Antimatter Factory, researchers create and guide antiprotons and antielectrons together to form antihydrogen, and all these antiparticles are analyzed to help scientists study the behavior of antimatter.

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

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.

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

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.

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.

Before 1932, when particle accelerators were first used for nuclear research, scientists relied on naturally radioactive substances to advance their understanding of the atomic nucleus.

View the winners of the 2025 Global Physics Photowalk contest

Participants were asked to submit entries showcasing particle physics labs from around the world, including particle accelerators, neutrino detectors, and superconducting experiments. The winning photograph was taken at the CryOgenic Laboratory for Detectors, where scientists hunt for dark matter after cooling materials to a few thousandths of a degree above absolute zero.

Fermilab's ICARUS experiment is searching for hypothetical sterile neutrinos

Neutrinos are a group of three chargeless, lightweight particles that can transform into one another via a quantum mechanical phenomenon called neutrino oscillations. The rate of these oscillations can be determined by measuring the amount of each type at different distances, where data inconsistencies would suggest the existence of new physics.

Play an incremental game that teaches the history of particle physics

Developed during the CERN Summer Student Webfest 2014, this game tasks you with building the reputation of your particle accelerator as you discover particles and hire staff to collect data. A historical breakdown accompanies each discovery, allowing you to recreate the timeline of the field.

Some cosmic rays possess energies as high as 100,000,000 teraelectron volts—more than 10 million times the energy of particles accelerated in the Large Hadron Collider.

Cyclotrons move particles in spiral paths of increasing radius

After particles are injected into the center of the device, an alternating electric field and a constant magnetic field energize the particles as they spiral outward toward a target. Cyclotrons are common in hospitals that perform molecular imaging, which relies on radioactive components that decay within hours.

The origin of the World Wide Web, plus a look at its first website and web browser

Invented by Tim Berners-Lee in 1989 while working at CERN—home of the world's largest particle physics laboratory—the Web was developed to facilitate the sharing of information among scientists at institutions worldwide. By the end of 1990, the first Web server was operational as a proof-of-concept on a NeXT workstation.

Explore the components of the linear particle accelerator at Los Alamos

Located at the site of bomb design and development for the Manhattan Project, LANSCE features an injector system for hydrogen ions, a series of tanks with alternating electric fields for proton acceleration, and an isotope production facility that creates radioisotopes for medical treatments.

If particle accelerators did create black holes by packing tremendous energy into a small volume, then trillions would be created in Earth's atmosphere daily by cosmic rays.

More than 97% of the world's particle accelerators are used for commercial purposes

Only a few hundred of the over 30,000 particle accelerators worldwide are used for research. Most are involved in medical imaging and treatment, food sterilization, semiconductor processing, cargo screening, and radioisotope production. They're also used to modify the properties of polymers.

Within ALICE—A Large Ion Collider Experiment—at the Large Hadron Collider, scientists have created quark-gluon plasma—an exotic form of matter present in the moments after the Big Bang.

As of 2025, LUX-ZEPLIN is the world's most sensitive dark matter experiment, which is designed to indirectly detect a potential candidate for the invisible form of matter.

Explaining the Higgs boson, also known as the 'God Particle'

The Higgs boson is a long sought after fundamental particle that—within the framework of high-energy physics—gives other particles their mass. Having captured public attention when it was discovered in 2012 at the Large Hadron Collider, and its...

The Curies developed a way to measure radioactivity in an old medical dissecting room

Despite lacking proper laboratory conditions, Marie and Pierre built an ionization chamber and a piezoelectric quartz electrometer to measure the amount of charged particles released by radiation, with a sensitivity of ten-trillionth of an ampere. Substances with different emission rates indicated different elements.

The Curies were buried in lead-lined coffins to contain their radioactive bodies

Their discoveries of polonium and radium involved ongoing exposure to radioactive materials before shielding technology was developed. Their notebooks, furniture, and other belongings remain radioactive today, requiring researchers to sign a waiver and wear protective clothing to access.

In 1971, a $35 ferret helped clean the Fermi National Accelerator Laboratory

Lacking cleaning robots, Fermilab scientists purchased a ferret named Felicia when metal slivers obstructing accelerated particles were identified. They trained her to run strings through vacuum tubes more than 90 meters long, and cleanser-dipped swabs were then tied to the strings and pulled through to remove the debris.

In 2026, researchers successfully transported antimatter in a truck using a portable trap that employed electromagnetic fields to hold 92 antiprotons.

The most common type of particle accelerator is a linear electron accelerator, which fires particles in a straight line, making them useful for the intense, targeted beams needed in cancer treatment.

The discovery of the neutron paved the way for nuclear weapons

In 1932, James Chadwick discovered the subatomic particle when trying to explain the radiation emitted by beryllium after it was bombarded with alpha particles. The radiation’s ability to eject protons from a target suggested a chargeless particle with slightly more mass than a proton.

Scientists have determined the properties of cosmic rays by analyzing their trajectories in bubble chambers—containers filled with a vapor that clings to charged particles.

The NSF funded the design and construction of LIGO by MIT and Caltech

The 1992 Cooperative Agreement between the National Science Foundation and both research institutions came twelve years after funding 1.5-meter (4.9-foot) and 40-meter (131-foot) prototypes. With a 1992 budget of $395M, LIGO was once one of the largest NSF-funded projects in history

Particle accelerators detect subatomic particles using millions of sensors

Calorimeters measure the energy of particles. Tracking devices can measure momentum and charge from the trajectory of particles, which is determined by recording tiny electrical signals. Time-of-flight detectors provide particle velocities directly and particle mass indirectly, giving physicists a suite of properties to compare with those of known matter.

LIGO is part of the advanced gravitational wave detector network

Like the Laser Interferometer Gravitational-wave Observatory, Europe's Virgo Gravitational Wave Interferometer and Japan's Kamioka Gravitational Wave Detector reflect laser beams down perpendicular tunnels to detect gravitational waves in the patterns created by the recombined waves. Future observatories are expected to contribute to this network, further improving gravitational wave detections.

View a ranking of the masses of fundamental particles, from the massless photon to the top quark, and a timeline of their discoveries.

Since 2017, Virgo has helped LIGO localize astronomical phenomena

The detector near Pisa, Italy, coordinates its experimental runs with those in Hanford, Washington, and Livingston, Louisiana. Scientists can triangulate the locations of celestial events that generate gravitational waves using signal arrival times, just as earthquake locations can be determined from measurements at three seismic stations.

The discovery of nuclear fission was facilitated by the discovery of the neutron

The discovery of the neutron provided scientists with a particle that could penetrate the nucleus and advance atomic physics. Otto Hahn was the sole Nobel recipient for the discovery of fission, despite collaborating with Lise Meitner and Fritz Strassmann.

Watch how the machine at the heart of NASA's Cold Atom Lab produces atoms near absolute zero—the coldest theoretical temperature in the universe—for experiments involving quantum phenomena.

As of 2023, the world's smallest particle accelerator is smaller than a penny

The prototype is an example of a photonic accelerator, which utilizes tiny lasers to accelerate electrons rather than relying on oscillating electromagnetic fields to move them. It can deliver about 1 electron per second with energies equivalent to those found in cathode-ray tube televisions.