High Quality Content by WIKIPEDIA articles! The Sacramento Regional Transit District, commonly referred to as RT, is the agency responsible for public transportation in the Sacramento, California area. It was established on April 1, 1973, as a result of the acquisition of the Sacramento Transit Authority. Along with about 60 bus routes, RT operates a large light rail system and connecting bus service in the Sacramento area, covering 418 sq mi (1,082.6 km2). It is currently the ninth busiest light rail system in the United States.