Super Proton Synchrotron

The Super Proton Synchrotron is a circular particle accelerator located at the border between France and Switzerland near Geneva. The facility uses more than 1000 electromagnets arranged in an underground tunnel to accelerate and steer particles to extreme speeds.

The facility started operating in 1976 and became known for discovering fundamental particles in the early 1980s. These discoveries led to groundbreaking understanding of how matter is structured at the smallest scales.

Scientists from numerous countries work at the Super Proton Synchrotron to conduct experiments in particle physics and advance understanding of matter.

The accelerator is not open for public tours inside the tunnel, but visitors can explore the facility grounds from outside. You can learn more about the research work by visiting the nearby exhibitions and information centers at the research campus.

The machine actually sits beneath two countries, with different sections of its tunnel in France and Switzerland. It can accelerate different types of particles beyond just protons, switching between lighter and heavier particles depending on what researchers need to study.