TRAX is a light rail system in the Salt Lake Valley of Utah, in the United States, serving Salt Lake City and many of its suburbs throughout Salt Lake County. Its full official name is Transit Express, though this name is very rarely used. The system is operated by the Utah Transit Authority (UTA). All TRAX trains are powered by overhead electrical wires.As of 2013 TRAX has three lines in service. The Blue Line provides service from Downtown Salt Lake City to Draper.