The Sacramento Regional Transit District, commonly referred to as SacRT (or simply 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. In addition to operating over 81 bus routes with connecting bus service in the Sacramento area covering 438 square miles (1,134.4 km2), SacRT also operates a large light rail system, which ranks currently as the sixteenth busiest light rail system in the United States. In 2021, the system had a ridership of 9,314,400, or about 39,400 per weekday as of the second quarter of 2022.