Particle accelerators. They are also used for

The Roman bridge of Salamanca, also known as Puente Mayor del Tormes and as Puente Prinçipal, is a Roman bridge crossing the Tormes River in the city of Salamanca, Castile and León, Spain. The bridge originally dates to the period of Roman occupation of the Iberian Peninsula, being built between 27BCE and 79CE and gave access to the southern part of the city. The bridge is part of the historic road known as the Vía de la Plata, passing between Mérida and Astorga. The bridge has had strategic, economic and cultural value to the region. The bridge has been rebuilt a number of times since its original construction, with the section on the right bank, to the city of Salamanca, retaining the majority of the original Roman construction.

A superconducting magnet is an electromagnet made from coils of superconducting wire. They must be cooled to cryogenic temperatures during operation. In its superconducting state the wire has no electrical resistance and therefore can conduct much larger electric currents than ordinary wire, creating intense magnetic fields. Superconducting magnets can produce stronger magnetic fields than all but the strongest non-superconducting electromagnets, and large superconducting magnets can be cheaper to operate because no energy is dissipated as heat in the windings. They are used in MRI instruments in hospitals, and in scientific equipment such as NMR spectrometers, mass spectrometers, fusion reactors and particle accelerators. They are also used for levitation, guidance and propulsion in a magnetic levitation (maglev) railway system being constructed in Japan.