The Blue Line is one of three light rail lines operated by the San Diego Trolley, an operating division of the San Diego Metropolitan Transit System. It currently operates between San Ysidro and Old Town in San Diego. Other Trolley lines include the Orange and Green lines.
The Blue line first opened between Centre City San Diego and San Ysidro in 1981, at a spartan cost of $86 million. In 1986, the line was named the South Line to differentiate it from the new East Line to Euclid Avenue. It was renamed the North-South Line when the Old Town extension opened in 1996. The North-South Line was renamed the Blue Line in 1997 with the opening of the extension to Mission San Diego.
With the introduction of the Green Line on 10 July, 2005, most Blue line service between Old Town and Qualcomm stadium was discontinued save for a few select rush hour trains. On 3 September, 2006 the Qualcomm service Blue line trains were discontinued entirely due duplication of service with Green Line service. All Blue line trains then terminated at the Old Town Transit Center.
Blue Line service also experienced some change in stations served. The Bayfront/E Street station in Chula Vista opened in 1985; about four years after service already operated along the tracks served. At the same time the Centre City station on C Street between 7th Avenue and 8th Avenue was eliminated. The Fenton Parkway stop opened in 2000; however, is now only served by the Green Line.
Because of the sharing of the track with freight traffic, stations along the southern end are sparsely furnished and do not feature concrete platforms like the rest of the system.