1. Home
  2.  ›
  3. Commuter Rail
  4.  ›
  5. Altamont Corridor Express

Altamont Corridor Express: Racing the Ridges Daily!

Last revised: September 6, 2024

By: Adam Burns

The Altamont Corridor Express commuter rail service, better known as simply ACE, is a relatively new operation inaugurated during the late 1990s.

It has become quite popular since its inception and currently utilizes Union Pacific trackage connecting Stockton and San Jose, California on a route that covers nearly 90 miles.

Thanks to the growth in ridership future plans are already in the works extending the system to Pittsburg (via Stockton) and a connection between Sacramento and Modesto. 

There are also long-term goals to include ACE within California's high-speed rail project.  All in all if you live in the San Francisco Bay area and the ACE is an option for you consider using their trains as it sure beats the rush of the highway.

Altamont Commuter Express F40PH-3C #3101 in Stockton, California on May 23, 1998. Bryan Copple photo. American-Rails.com collection.

The Altamont Commuter Express, named for the Altamont Pass in which the Union Pacific line operates between Stockton and San Jose, has its beginnings dating as far back as 1997. 

The state of California has long been a proponent of commuter rail service and there are currently multiple systems in operation ranging from Amtrak California to Amtrak's Surfliner, both of which receive state subsidies. 

During May of 1997 the San Joaquin Regional Rail Commission (SJRRC), Alameda Congestion Management Agency (ACCMA), and Santa Clara Valley Transportation Authority (VTA) came together to form what was then known as the Altamont Commuter Express (ACE). 

This new commuter rail service, covering 81 miles, would connect Stockton with San Jose.

While ACE would operate over Union Pacific trackage the history of line can be traced back to the historic Western Pacific, acquired by UP in 1982. 

The WP, also known as the "Feather River Route," was a regional Class I system incorporated on March 3, 1903.  It was the dream of Arthur Keddie, who saw the railroad a reality after receiving millions in financial backing from noted tycoon George Gould. 

Altamont Corridor Express F40PH-3C #310 is near Alviso, California with train #6 during November of 2012. Doug Kroll photo.

Keddie envisioned a system that would compete against the much larger Southern Pacific by connecting the San Francisco Bay Area with Salt Lake City utilizing the rugged Feather River Canyon. 

The road was completed and opened for service on November 1, 1909. 

In time the WP grew into a system reaching such locations as San Jose, Modesto, Woodland, and Bieber in California although its most important route was always the San Francisco/Oakland-Salt Lake City main line.

Altamont Commuter Express F40PH-2C #3101 leads westbound train #5 towards San Jose as it travels through rural Alviso, California on the morning of November 9, 2012. Doug Kroll photo.

The WP is perhaps best remembered for operating the legendary (original) California Zephyr, which covered much of the same territory as the current ACE. 

That famous train, however, was  discontinued after March 22, 1970.  During its first few years of service ACE witnessed strong growth although the mini-recession brought on by the Dot Com Bubble saw ridership decline in 2002. 

It quickly rebounded but again declined during the recession of late 2007.  However, since 2010 patronage has once more been on the rise and will likely continue to show strong grow if California completes its much anticipated high speed rail project. 

The current ACE system serves ten stations and connects with three other commuter/light rail systems which include Amtrak’s Capitol Corridor (Fremont), Amtrak's San Joaquin (Stockton), the Bay Area Rapid Transit (Fremont), and Caltrain (San Jose and Santa Clara).

The stations served include (from west to east) San Jose, Santa Clara, Great America, Fremont, Pleasanton, Livermore, Vasco, Tracy, Lathrop/Manteca, and finally Stockton. 

There are currently eight daily trains operated by Altamont Corridor Express:

  • #1, #3, #5, and #7 are westbound morning runs departing Stockton between 4 and 7 AM with arrivals in San Jose between 6:30 and just after 9 AM.

  • Conversely, eastbounds #2, #4, #6, and #8 leaves San Jose between 3:30 and 6:30 PM with arrivals back in Stockton throughout the evening hours (for complete scheduling information please visit the ACE website).  

Naturally, such times are meant to coincidence with the weekday work schedules, getting folks where they need to be in the morning and returning them home every night. 

Altamont Corridor Express F40PH-3C #3106 is in pusher service with evening train #04 at Santa Clara, California on November 9, 2012. Doug Kroll photo.

For a state with such crowded freeways as California commuter rail systems like ACE are very convenient (and less stressful). 

If you ride the entire Corridor, the trip is about two hours with trains reaching speeds as high as 79 mph.  According to the California's Department of Transportation ACE ridership currently exceeds 700,000 annually but this number is somewhat below its all-time high of 805,257 during the 2007-2008 year. 

Interestingly, ACE perennially sees the lowest ridership of all California's commuter rail operations (not including the state-aided Amtrak services).

However, overall numbers are strong considering it owns only 6 locomotives (five F40PH-2C's and one F40PH-3C) as well as 25 Bombardier-built Bi-Level commuter cars (nine of these are cab-control cars, which enable the train to operate in a push/pull setup, eliminating the need of turning the consist).

Altamont Commuter Express F4OPH-3C #3101 and its all-matching bi-level cars makes a station stop in Lathrop, California on October 21, 2005. Doug Kroll photo.

Additionally, the Corridor offers perhaps the scenic commuter trip anywhere in the state as it passes over Altamont Pass and through rural farmland during its journey to and from San Jose. 

In any event, it should never be forgotten that commuter rail is an expensive proposition and always has been going back to the days of private operation long before Amtrak and other state agencies were put into service. 

Year-to-year ACE normally covers only about 30% of its total cost, leaving taxpayers to foot the bill for the other millions in annual expenses (operating and administrative costs). 

In 2013 Altamont Commuter Express was renamed Altamont Corridor Express, perhaps in an effort to better associate it with as part of the state's future high-speed rail service. 

It will certainly be interesting to see the future of the ACE system and how ridership will be affected if the new operation is completed.

Recent Articles

  1. North Carolina - Whiskey Tasting - Train Rides

    Jun 14, 26 01:13 PM

    98237123141425128766.jpg
    One of the GSMR's most distinctive special events is Spirits on the Rail, a bourbon-focused dining experience built around curated drinks and a chef-prepared multi-course meal.

    Read More

  2. Connecticut - Whiskey Tasting - Train Rides

    Jun 14, 26 12:55 PM

    92374265346527667893789089.jpg
    While the Naugatuck Railroad runs a variety of trips throughout the year, one event has quickly become a “circle it on the calendar” outing for fans of great food and spirited tastings: the BBQ & Bour…

    Read More

  3. Utah - Wine Tasting - Train Rides

    Jun 14, 26 12:46 PM

    483065061_1043090677854796_6203365029670081509_n.jpg
    Utah, a state widely celebrated for its breathtaking natural beauty and dramatic landscapes, is also gaining recognition for an unexpected yet delightful experience: wine tasting trains.

    Read More

  4. Vermont - Wine Tasting - Train Rides

    Jun 14, 26 12:42 PM

    9127361234612478125985666.jpg
    Known for its stunning green mountains, charming small towns, and burgeoning wine industry, Vermont offers a unique experience that seamlessly blends all these elements: wine tasting train rides.

    Read More

  5. Rhode Island - Wine Tasting - Train Rides

    Jun 14, 26 12:39 PM

    917823716235152351624615899866.jpg
    It may the smallest state but Rhode Island is home to a unique and upscale train excursion offering wide aboard their trips, the Newport & Narragansett Bay Railroad.

    Read More

  6. Maryland - Murder Mystery - Dinner Train Rides

    Jun 14, 26 12:06 PM

    91724176524124615878926908707.jpg
    Maryland is known for its scenic landscapes, historical landmarks, and vibrant culture, but did you know that it’s also home to some of the most thrilling murder mystery dinner trains?

    Read More

  7. Minnesota - Murder Mystery - Dinner Train Rides

    Jun 14, 26 11:46 AM

    987582745782689897890098.jpg
    Murder mystery dinner trains offer an enticing blend of suspense, culinary delight, and perpetual motion, where passengers become both detectives and dining companions on an unforgettable journey.

    Read More

  8. Georgia - Murder Mystery - Dinner Train Rides

    Jun 14, 26 11:07 AM

    8654sart8789755767.jpg
    In the heart of the Peach State, a unique form of entertainment combines the thrill of a murder mystery with the charm of a historic train ride.

    Read More

  9. Ohio - Wine Tasting - Train Rides

    Jun 13, 26 11:20 AM

    54063270967_8ea485da9a_k.jpg
    Among the intriguing ways to experience Ohio's splendor is aboard the wine tasting trains that journey through some of Ohio's most picturesque vineyards and wineries.

    Read More

  10. Pennsylvania - Wine Tasting - Train Rides

    Jun 13, 26 11:14 AM

    912743174352378268979008.jpg
    Wine tasting trains are a unique and enchanting way to explore the state’s burgeoning wine scene while enjoying a leisurely ride through picturesque landscapes.

    Read More

  11. Maryland ~ Whiskey Tasting ~ Train Rides

    Jun 13, 26 10:51 AM

    891731525124721752896887667.jpg
    You can enjoy whiskey tasting by train at just one location in Maryland, the popular Western Maryland Scenic Railroad based in Cumberland.

    Read More

  12. California ~ Whiskey Tasting ~ Train Rides

    Jun 13, 26 10:46 AM

    75142371258712978185723872566.jpg
    There is currently just one location in California offering whiskey tasting by train, the famous Skunk Train in Fort Bragg.

    Read More

  13. Colorado - Murder Mystery - Dinner Train Rides

    Jun 13, 26 10:34 AM

    10821872472148723598238746893.jpg
    Nestled among the breathtaking vistas and rugged terrains of Colorado lies a unique fusion of theater, gastronomy, and travel—a murder mystery dinner train ride.

    Read More

  14. South Dakota - Murder Mystery - Dinner Train Rides

    Jun 13, 26 10:27 AM

    44769036_2007471786211415_7062575978807033856_n.jpg
    While the state currently does not offer any murder mystery dinner train rides, the popular 1880 Train at the Black Hills Central recently hosted these popular trips!

    Read More

  15. North Carolina - Father's Day - Train Rides

    Jun 12, 26 02:16 PM

    900097155325465786867.jpg
    Celebrating dad on a scenic train in North Carolina can be found at the New Hope Valley Railway which hosts a special event for the day.

    Read More

  16. Alabama - Father's Day - Train Rides

    Jun 12, 26 02:10 PM

    001823615235125656788686866.jpg
    Alabama, with its rich railway heritage and scenic countryside, is a wonderful way to experience by train. One location even hosts a special trip for Father's Day!

    Read More

  17. Oregon - Wine Tasting - Train Rides

    Jun 12, 26 02:03 PM

    19i271723471247127417815196566.jpg
    For those looking to explore this wine paradise in style and comfort, Oregon's wine tasting trains offer a unique and enjoyable way to experience the region's offerings.

    Read More

  18. Virginia - Wine Tasting - Train Rides

    Jun 12, 26 01:57 PM

    1897247146124712579892586806.webp
    Wine tasting trains in Virginia provide just that—a unique experience that marries the romance of rail travel with the sensory delights of wine exploration.

    Read More

  19. Wisconsin - Murder Mystery - Dinner Train Rides

    Jun 12, 26 01:43 PM

    124981724762157892785298689667.jpg
    Whether you're a fan of mystery novels or simply relish a night of theatrical entertainment, Wisconsin's murder mystery dinner trains promise an unforgettable adventure.

    Read More

  20. Alabama ~ Murder Mystery ~ Dinner Train Rides

    Jun 12, 26 01:34 PM

    1249781235723587298382906986.jpg
    There is currently one location in the state offering a murder mystery dinner experience, the Wales West Light Railway!

    Read More

  21. South Park Rail Society Acquires Como Roundhouse

    Jun 11, 26 11:47 PM

    IMG_3487.jpeg
    The South Park Rail Society has announced it has purchased the former Denver, South Park & Pacific roundhouse in Como, Colorado.

    Read More

  22. Missouri Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 05:01 PM

    12978o000812746236667.jpg
    The state of Missouri offers spectacular fall foliage located in the Ozark Mountains. Enjoy a train ride to view the colors at the Branson Scenic Railway.

    Read More

  23. Maine Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 03:51 PM

    40276128585_8c43f54a86_o.jpg
    Find out where you can board a train to view Maine's fall colors here!

    Read More

  24. Virginia Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 03:34 PM

    91824283653257828639207388.jpg
    Visit the Buckingham Branch Railroad in Dillwyn to view the region's fall colors by train. Learn more about their trips here!

    Read More

  25. Michigan Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 01:19 PM

    40461162401_7c758199da_o.jpg
    This guide highlights organizations in Michigan hosting train rides during the fall season.

    Read More

  26. New York Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 01:10 PM

    7908912761556617862697090980.jpg
    Presented here is a directory of current organizations hosting fall foliage train rides in the state of New York.

    Read More

  27. Vermont Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 01:03 PM

    87126651274283596096024362346.jpg
    Vermont is one of the great states in New England to view the fall colors in the Green Mountains. See them by train at the Green Mountain Railroad.

    Read More

  28. Minnesota Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 11:09 AM

    12487123875872135866.jpg
    Interested in a train ride to see the fall colors in Minnesota? Check out the North Shore Scenic Railroad in Duluth.

    Read More

  29. Kentucky Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 10:10 AM

    krym_am.jpg
    There are several heritage railroads in Kentucky which host excursions through the autumn season! Learn more about these trips here.

    Read More

  30. Pennsylvania Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 09:54 AM

    53474465924_e0fff3fa10_k.jpg
    From the Allegheny Mountains in the west to the Pocono Mountains in the northeast, there are many spectacular fall foliage train rides in Pennsylvania.

    Read More

  31. Ohio Fall Foliage Train Rides (2026): A Complete Guide

    Jun 11, 26 09:49 AM

    54064522179_c7d7861cc9_k.jpg
    Located in the eastern Appalachian foothills, Ohio's beautiful rolling countryside offers spectacular fall colors that can be viewed by train. Learn more here.

    Read More

  32. Rhode Island Fall Foliage Train Rides (2026): A Complete Guide

    Jun 10, 26 11:35 PM

    178247823752893587234685234603466.jpg
    Enjoy the breathtaking fall colors of New England at Newport & Narragansett Bay Railroad in Rhode Island. Learn more about their trips here.

    Read More

  33. Washington Fall Foliage Train Rides (2026): A Complete Guide

    Jun 10, 26 10:49 PM

    43039237145_0b10864e3d_k.jpg
    Learn more about locations in Washington offering fall foliage train rides. They currently include the Mount Rainier Scenic and Chelatchie Prairie railroads.

    Read More

  34. Maryland Fall Foliage Train Rides (2026): A Complete Guide

    Jun 10, 26 04:27 PM

    19933031op1bn47373849o22487.jpg
    View the gorgeous Appalachian Mountains by train in western Maryland via the Western Maryland Scenic Railroad. Learn more about their trips here!

    Read More

  35. Oregon Fall Foliage Train Rides (2026): A Complete Guide

    Jun 10, 26 04:23 PM

    283527358239856.jpg
    Discover all of the locations in Oregon hosting train rides specifically tailored towards viewing the fall colors.

    Read More

  36. Utah - Murder Mystery - Dinner Train Rides

    Jun 10, 26 01:16 PM

    0182431872456124625782568926897.jpg
    This article highlights the murder mystery dinner trains currently avaliable in the state of Utah!

    Read More

  37. Rhode Island - Murder Mystery - Dinner Train Rides

    Jun 10, 26 12:56 PM

    9127341246125828753263582539866.jpg
    Let's dive into the enigmatic world of murder mystery dinner train rides in Rhode Island, where each journey promises excitement, laughter, and a challenge for your inner detective.

    Read More

  38. Massachusetts 'Father's Day' Train Rides

    Jun 10, 26 12:46 PM

    818271263612364175896966.jpg
    The Cape Cod Central is the one location in the state hosting an event just for dads, a special brunch train. Learn more here!

    Read More

  39. New Jersey 'Father's Day' Train Rides

    Jun 10, 26 12:34 PM

    172361264615675855.jpg
    There are a few locations in New Jersey celebrating dads with a train ride. Learn more about these unique trips here!

    Read More

  40. Pennsylvania 'Father's Day' Train Rides

    Jun 10, 26 12:30 PM

    871247124621427889368907907098.jpg
    This state offers a unique way to celebrate Father's Day with unforgettable train rides that combine history, stunning landscapes, and a dash of nostalgia.

    Read More

  41. Delaware & Hudson Diesel Roster (All-Time)

    Jun 10, 26 12:18 PM

    098765rfdcew323456tyhji87898uy.jpg
    Long tied to Alco’s Schenectady plant on its own lines, the D&H boasted an almost exclusively Alco first-generation fleet although did settle for some GE products later on.

    Read More

  42. Tennessee - Wine Tasting - Train Rides

    Jun 09, 26 02:46 PM

    918274317624612642613578269677.jpg
    One of the most unique and enjoyable ways to savor the flavors of Tennessee’s vineyards is by train aboard the Tennessee Central Railway Museum.

    Read More

  43. New York 'Father's Day' Train Rides

    Jun 09, 26 02:27 PM

    55069085274_33fdc82ad1_k.jpg
    If you’re looking to make this day memorable, consider taking a scenic train ride with your dad through the beautiful landscapes of New York State.

    Read More

  44. Texas "Father's Day" Train Rides

    Jun 09, 26 02:20 PM

    81827162352155556627582966.jpg
    In Texas, Father's Day can be made unique by combining the nostalgia and charm of train rides with the grandeur of the Texas landscape.

    Read More

  45. MBTA Unveils Heritage GP40MC-3 1776 For America 250

    Jun 09, 26 02:07 PM

    The Massachusetts Bay Transportation Authority (MBTA) has joined a growing list of railroads honoring America’s upcoming Semiquincentennial with the unveiling of its striking new heritage locomotive…

    Read More

  46. Grand Canyon Railway Unveils 'America 250' Locomotive

    Jun 09, 26 01:49 PM

    283283582332840693059050974.jpg
    The Grand Canyon Railway recently unveiled its own 'America 250' locomotive, F40FH #365 draped in a patriotic red, white and blue livery with the Grand Canyon flanking the rear of the engine.

    Read More

  47. CSX Unveils Two Patriotic America250 Heritage Locomotives

    Jun 09, 26 12:01 PM

    2352035923572367777236578966.jpg
    CSX Transportation has joined the growing roster of Class I railroads honoring America’s upcoming 250th anniversary (Semiquincentennial) with the unveiling of two specially painted commemorative locom…

    Read More

  48. Union Pacific 4547 Hauls Artemis III Rocket Components

    Jun 09, 26 09:29 AM

    9782847128523689896903747.jpg
    In a striking display of American innovation, infrastructure, and ambition, Union Pacific’s newest commemorative locomotive, No. 4547, departed on its first revenue freight assignment, carrying solid…

    Read More

  49. Washington - Murder Mystery - Dinner Train Rides

    Jun 08, 26 12:25 PM

    912734812478923958785289666.jpg
    This article delves into what makes murder mystery dinner train rides in Washington State such a captivating experience.

    Read More

  50. Nevada - Murder Mystery - Train Rides

    Jun 08, 26 12:05 PM

    6169506375_2b49d6078c_o.jpg
    Seamlessly blending the romance of train travel with the allure of a theatrical whodunit, these excursions promise suspense, delight, and an unforgettable journey through Nevada’s heart.

    Read More