Caltrain (AAR reporting marks JPBX) is a California commuter rail line on the San Francisco Peninsula an the Santa Clara Valley in the United States. It is currently operated under contract by Amtrak and funded jointly by City and County of San Francisco, San Mateo County Transit District, and Santa Clara Valley Transportation Authority through the Peninsula Corridor Joint Powers Board. The northern terminus of the rail line is in San Francisco, at 4th and King streets; its southern terminus is in Gilroy. Trains operate out of San Francisco and San Jose on a half hourly basis every weekday, with more frequent service provided during commute hours. Service between San Jose and Gilroy is limited to three daily commute-hour round trips. Average weekday ridership in February 2008 was 36,993 persons.