Future phases will add stations at Pajaro/Watsonville and Castroville, with the potential for up to six daily round trips. The length of the Caltrain line from Gilroy to San Francisco is part of the planned route of the California High-Speed Rail line. Trains are predicted to travel at speeds up to between San Jose and San Francisco.With the adaptation of preferred alternative in July 2019 on the San Jose to Gilroy HSR section, dedicated HSR tracks are planned south of Gilroy station, while HSR would share tracks with Caltrain between San Francisco and Gilroy. The Caltrain right of way between San Francisco and Tamien stations is owned and maintained by its operating agency, the Peninsula Corridor Joint Powers Board (PCJPB). PCJPB purchased the right of way from Southern Pacific (SP) in 1991, while SP maintained rights to inter-city passenger and freight trains. In exchange SP granted PCJPB rights to operate up to 6 trains per day between Tamien and Gilroy stations, later increased to 10 trains per day on a deal with SP's successor Union Pacific (UP) in 2005. The system has 32 stations, 29 served daily and two weekend-only. San Francisco 4th and King Street is the northern terminus of the system, while Gilroy is the southern terminus. Atherton and Broadway are served only on weekends, and Stanford is served only on Stanford University's football game days. College Park is served only on weekdays during Bellarmine College Preparatory's school commute time. Tamien is served by train on weekdays and by shuttle bus on weekends. The five southernmost stations—Capitol, Blossom Hill, Morgan Hill, San Martin, and Gilroy—are served only on weekdays during commute time. Twelve stations are served by the express train service known as Baby Bullet, inaugurated in 2004. Two stations, Sunnyvale and Santa Clara, are not long enough to accommodate six-car trains without minor service impacts. Seven stations (Millbrae, Burlingame, San Carlos, Menlo Park, Palo Alto, Santa Clara, and San Jose Diridon) are listed on the National Register of Historic Places. The Southern Pacific Railroad originally built many stations with a side platform on the west side of the tracks to serve southbound trains, plus a narrow island platform between tracks to serve northbound trains. To protect northbound passengers from being struck by southbound trains, Caltrain implemented a "hold-out rule" (GCOR 6.30): if a train is stopped for passengers, an approaching train in the opposite direction on the other track must wait outside the station.