The Green Line is the third line in the San Diego Trolley system with service beginning on July 10, 2005, upon the completion and opening of the 5.9 miles (9.5 km) Mission Valley East extension. History Siemens S70 Green Line train at SDSU's underground station, on the station's opening day (July 10, 2005) The line is one of four lines in the Trolley system, the others being the Blue, Orange, and Silver lines. The Green Line has the second highest ridership of the San Diego Trolley's three regular lines, transporting 13,673,926 riders during FY 2014 according to the MTS. The route serves Downtown San Diego, Mission Valley, and the cities of La Mesa, El Cajon, and Santee. an operating division of the San Diego Metropolitan Transit System (MTS). The Green Line is a 23.6-mile (38.0 km) light rail line in the San Diego Trolley system, operated by San Diego Trolley, Inc.
