Altamont Commuter Express is a small commuter rail system connecting Stockton with San Jose and Silicon Valley. ACE served an average of 2,500 riders each weekday during the fourth quarter of 2009 via 10 stations on about 86 miles of track. The entire route from Stockton to San Jose Diridon Station takes about 2 hours and 10 minutes.
Currently, there are three trains each weekday in each direction – in the morning, trains depart Stockton for San Jose, and in the evening, trains depart San Jose for Stockton. In some special service such as for Oakland Raiders home games, trains will serve the Oakland Coliseum.
Fares are distance-based, and the current adult fare from Stockton to San Jose is $11.75. ACE uses GM Electro-Motive F40PH locomotives and Bombardier bi-level coaches.
ACE is currently considering expansion projects, including a potential Modesto to Sacramento service. As a part of the California High Speed Rail project, the corridor could see several upgrades including more frequent service and electrification.