Joint European Torus, Nuclear fusion research facility in Culham, United Kingdom

The Joint European Torus is a nuclear fusion research facility in Culham, United Kingdom, consisting of a large toroidal chamber surrounded by magnets. The inner chamber is lined with heat-resistant tiles and monitored by hundreds of instruments that measure temperature and plasma movements.

Construction began in 1982, and the first plasma experiments took place here on June 25, 1983. In 1991, researchers succeeded in producing controlled fusion reactions, marking a turning point in the history of fusion energy.

Researchers from across Europe work together here, following experiments from a control room that rises several stories. The shared use of the site has created an international community of physicists and engineers who exchange data regularly.

The site sits in a rural area near Abingdon and is open to public tours only at certain times. Visitors need to register in advance because of security checks and limited places available.

In December 2021, the facility produced 59 megajoules of fusion energy during a five-second pulse. This result surpassed its own record from 1997 and showed that improvements made to the chamber and magnets had worked.