Between the spring of 1971 and the summer of 1972, passengers traveling between Chicago and Oakland would have to travel on two different trains: the Denver Zephyr, which operated daily between Chicago and Denver, and the City of San Francisco, which operated three times a week, between Denver and the San Francisco Bay Area.
Eventually, however, after several false starts, Amtrak consolidated the two trains into one, dubbed the San Francisco Zephyr, homage to both the California Zephyr and the San Francisco Chief, between Chicago and Oakland.
The Rio Grande continued to operate the Rio Grande Zephyr between Denver and Ogden.

In 1983, the D&RGW elected to join Amtrak, citing increasing losses in passenger operations.
Amtrak re-routed the San Francisco Zephyr over the D&RGW's Moffat Subdivision between Denver and Salt Lake City, its original preference from 1971.
The change was scheduled for April 25, but a mudslide at Thistle, Utah, closed the line and delayed the change until July 16.
With the change of route, Amtrak renamed the train as the California Zephyr.
The modern California Zephyr uses mostly the same route as the original east of Winnemucca, Nevada.
The train uses the route of the former City of San Francisco, along the Overland Route (First Transcontinental Railroad), between Elko, Nevada, and Sacramento.
Across central Nevada, the two rail lines have been combined to use directional running.
As such, the exact spot the train switches lines depends on the direction of travel.

For most of the 1980s and 1990s, the California Zephyr operated in tandem with the Seattle-bound Pioneer and Los Angeles-bound Desert Wind.
Since 1980, the PIoneer and Desert Wind had exchanged through coaches with the San Francisco Zephyr at Ogden.
The exchange point was moved to Salt Lake City when the latter train became the California Zephyr.
This created a massive train of 16 Superliner cars running from Chicago to Utah, easily the longest train Amtrak had operated outside of the Auto Train.
Amtrak required at least four EMD F40PH locomotives to pull this behemoth over the steep grades of the Moffat subdivision.
To ease the load, Amtrak began splitting the Pioneer from the Zephyr and Desert Wind at Denver in 1991, while the Desert Wind continued splitting from the Zephyr at Salt Lake City.
The Pioneer and Desert Wind were both discontinued in 1997.

The western terminus of the train was cut back to Emeryville station when Oakland Central station was closed on August 5, 1994.
The California Zephyr was re-extended to Oakland with the opening of the Jack London Square station on May 12, 1995.
However, this required a complicated reverse move along street running tracks to reach the wye at West Oakland.
The train was cut back again to Emeryville on October 26, 1997.

Service between Reno and Denver was suspended for about a month in April 2020, as part of a round of service reduction in response to the coronavirus pandemic.
Between the spring of 1971 and the summer of 1972, passengers traveling between Chicago and Oakland would have to travel on two different trains: the Denver Zephyr, which operated daily between Chicago and Denver, and the City of San Francisco, which operated three times a week, between Denver and the San Francisco Bay Area. Eventually, however, after several false starts, Amtrak consolidated the two trains into one, dubbed the San Francisco Zephyr, homage to both the California Zephyr and the San Francisco Chief, between Chicago and Oakland. The Rio Grande continued to operate the Rio Grande Zephyr between Denver and Ogden.
In 1983, the D&RGW elected to join Amtrak, citing increasing losses in passenger operations. Amtrak re-routed the San Francisco Zephyr over the D&RGW's Moffat Subdivision between Denver and Salt Lake City, its original preference from 1971. The change was scheduled for April 25, but a mudslide at Thistle, Utah, closed the line and delayed the change until July 16. With the change of route, Amtrak renamed the train as the California Zephyr. The modern California Zephyr uses mostly the same route as the original east of Winnemucca, Nevada. The train uses the route of the former City of San Francisco, along the Overland Route (First Transcontinental Railroad), between Elko, Nevada, and Sacramento. Across central Nevada, the two rail lines have been combined to use directional running. As such, the exact spot the train switches lines depends on the direction of travel. 
For most of the 1980s and 1990s, the California Zephyr operated in tandem with the Seattle-bound Pioneer and Los Angeles-bound Desert Wind. Since 1980, the PIoneer and Desert Wind had exchanged through coaches with the San Francisco Zephyr at Ogden. The exchange point was moved to Salt Lake City when the latter train became the California Zephyr. This created a massive train of 16 Superliner cars running from Chicago to Utah, easily the longest train Amtrak had operated outside of the Auto Train. Amtrak required at least four EMD F40PH locomotives to pull this behemoth over the steep grades of the Moffat subdivision. To ease the load, Amtrak began splitting the Pioneer from the Zephyr and Desert Wind at Denver in 1991, while the Desert Wind continued splitting from the Zephyr at Salt Lake City. The Pioneer and Desert Wind were both discontinued in 1997.
The western terminus of the train was cut back to Emeryville station when Oakland Central station was closed on August 5, 1994. The California Zephyr was re-extended to Oakland with the opening of the Jack London Square station on May 12, 1995. However, this required a complicated reverse move along street running tracks to reach the wye at West Oakland. The train was cut back again to Emeryville on October 26, 1997.
Service between Reno and Denver was suspended for about a month in April 2020, as part of a round of service reduction in response to the coronavirus pandemic.
California Zephyr