The TGV (French: Train à Grande Vitesse, "high-speed train") is France's high-speed rail service, operated by SNCF Voyages, the long-distance rail branch of SNCF, the national rail operator.It was developed during the 1970s by GEC-Alsthom (now Alstom) and SNCF. Originally designed as turbotrains to be powered by gas turbines, the prototypes evolved into electric trains with the 1973 oil crisis.