Special Event Line (San Diego Trolley)

The Special Event Line, also known as the "Red Line" until 2012, was a light rail line operated by the San Diego Trolley, an operating division of the San Diego Metropolitan Transit System. This line operated twice, but only during special events.

The first time, from at least 2007 to 2012, the Red Line operated between Gaslamp Quarter station and the Qualcomm Stadium station (now known as Stadium station). They operated once every 15 minutes, during sporting events at Petco Park Qualcomm Stadium, Cox Arena, and the SDSU Open Air Theater (OAT), as well as selected conventions and other major city events (such as the San Diego Comic-Con).

On maps issued during its first tenure in operation, the Red Line was illustrated as a red dashed line, indicating that it was a "Special Event Service Only".

The Special Event Line was discontinued in 2012, as part of the Trolley Renewal Project. The entire route the Special Event line ran is now served by the Green Line (which had been extended from Old Town to 12th & Imperial), and MTS now opts to add cars and increase service on that route when needed.

The last Special Event Trolley departed at 6:54 pm on August 29, 2012.

From July 20 to July 24, 2022 (during ComicCon), the Special Events Line was brought back to run from Balboa Avenue Transit Center to 12th and Imperial, following the Green Line's alignment from 12th and Imperial to Santa Fe Depot.

Later, from July 21 to July 24, 2023, the Special Events Line was revived along the 2022 route. Over the course of that weekend, the Special Events Line served over 100 thousands riders.