The Santa Fe 2900 Class was a series of 30 4-8-4 type steam locomotives built between 1943 and 1944 for Atchison, Topeka and Santa Fe Railroad and pulled freight and passenger trains until retirement in the early to late-1950s.

When it was fully restored in July 2021, it is considered to be the largest operating 4-8-4 type steam locomotive in the United States.

[1] Between 1946 and 1948, they were then approved for 110 mph speeds with the Santa Fe's express passenger trains after being fitted with Timken roller bearing tandem side-rods, up from 100-mph when delivered with its original side-rods.

However, anecdotes from retired drivers have hinted that the class was able to run at speeds of over 120 mph for miles.

After the war, they hauled passenger trains such as the Chief, Scout and Grand Canyon Limited.