Photo: DJTechYT / Wikimedia Commons (CC BY-SA 4.0)
The San Diego Trolley, run by the Metropolitan Transit System (MTS), is the backbone of public transit in the southern half of the county. It connects the border at San Ysidro with downtown, Old Town, Mission Valley, San Diego State University, UC San Diego and East County.
The lines
- UC San Diego Blue Line: San Ysidro to downtown, Old Town and on to the UC San Diego area and University City, via the Mid-Coast extension.
- Orange Line: downtown through Lemon Grove and La Mesa to El Cajon.
- Green Line: from the downtown waterfront through Old Town, Mission Valley and SDSU to El Cajon.
- Copper Line: the East County Connector, which began service on Sept. 29, 2024, running every 15 minutes for most of the day between El Cajon Transit Center, Arnele, Gillespie Field and Santee. It replaced Green and Orange line service north of El Cajon.
Paying with PRONTO
MTS and North County Transit District use PRONTO, a reloadable card and mobile app. Fares are capped: once your rides add up to the price of a day or monthly pass, further rides in that period are free. Reduced fares are available to seniors, people with disabilities and Medicare cardholders.
Free rides for 18 and under
Through the Youth Opportunity Pass pilot, sponsored by SANDAG and the County of San Diego, riders 18 and under ride MTS and NCTD buses and trains free with a Youth PRONTO app account or card. The pilot began May 1, 2022, and has been extended through June 30, 2027. Children 5 and under always ride free.
North County
North County Transit District runs the COASTER commuter train along the coast between Oceanside and downtown San Diego, and the SPRINTER between Oceanside and Escondido.
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