The California Zephyr is a passenger train operated by Amtrak between Chicago Union Station in Chicago, Illinois and Emeryville, California. The distance traveled is 2,479 miles(3,989 kilometers) and is Amtrak's second longest route in the U.S after the Texas Eagle. Average journey time is approximately 55 hours(2 days 7 hours). The first train was in two a branch that ran Chicago-Denver and then with a layover in Denver a train to Oakland, CA later came. The train had rail hostesses called Zephyrites. They had to change the route in the 1940's but it returned to it's original route in 1971.

The westbound train leaves Chicago in the mid afternoon and it crosses the Mississippi River and speeds through Iowa with an arrival in Denver by breakfast and t then climbs the Rockies and goes into Salt Lake City where from there I-80 is followed