Amtrak is canceling trains as railroad unions prepare to strike, throwing the rail network into chaos see the full list of changes

• Amtrak suspended some cross-country routes Tuesday due to an impending rail worker strike.
• Some trains departing from Chicago, Seattle, San Francisco, Los Angeles, and San Antonio were canceled.

Amtrak suspended some of its most storied and picturesque routes on Tuesday in preparation for an impending rail worker strike that could further upend supply chains and damage the US economy.

Tuesday departures for the Southwest Chief, Empire Builder, California Zephyr, and a portion of the Texas Eagle routes have all been pre-emptively canceled in order to avoid passenger disruptions, an Amtrak spokesperson told Insider.

If freight rail carriers do not reach a resolution with two major worker unions, shorter state-supported routes could also be canceled this week, the spokesperson added.

While Amtrak itself is not involved in the union negotiations, its trains travel on 21,000 miles of track throughout the Midwest and western US — nearly all of which is owned, maintained, and controlled by freight railroads. As a result, a freight rail worker strike would "significantly impact intercity passenger rail service," Amtrak said.

Most travel within Amtrak's owned-and-operated Northeast Corridor between Boston, New York, and Washington would not be affected by the potential strike, as they do not operate on freight rail tracks. The higher-speed Acela line will operate a full schedule and only a small number of Northeast Regional departures would be impacted by any strike, Amtrak said.

Passengers whose trips are affected by these changes will be able to change their reservation to another travel date, waiving any difference in fare for departures through Oct. 31, or receive a full refund without cancelation fees.

Here's the full list of train departures impacted by Tuesday's cancelations:

Southwest Chief: Chicago to Los Angeles

Amtrak Southwest Chief route map      Amtrak

Amtrak's Southwest Chief route runs from Chicago to Los Angeles. The 40-hour-plus train ride includes stops in Arizona, New Mexico, Colorado, Kansas, and Missouri.

All trains departing Tuesday from Chicago and Los Angeles along this route have been canceled.

Empire Builder: Chicago to Seattle/Portland

Amtrak Empire Builder route      Amtrak

Amtrak's Empire Builder route runs from Chicago to Seattle, with major stops in Minneapolis, Spokane, and Portland.

All trains departing Tuesday from Chicago and Seattle along this route have been canceled.

California Zephyr: Chicago to San Francisco

California Zephyr Amtrak route map      Amtrak

Amtrak's California Zephyr route runs between Chicago and San Francisco, with major stops in Omaha, Denver, and Salt Lake City along the way.

All trains departing Tuesday from Chicago and San Francisco along this route have been canceled.

Los Angeles to San Antonio portion of the Texas Eagle route

Texas Eagle route (Los Angeles to San Antonio) Amtrak map      Amtrak

Amtrak has canceled trains departing Tuesday from Los Angeles and San Antonio along a portion of the Texas Eagle route. The remainder of the route is not currently impacted by these changes.