Chicago, Burlington and Quincy 4000
Chicago, Burlington and Quincy 4000, also known as Aeolus, is a preserved S-4A class 4-6-4 "Hudson" steam locomotive that was originally built by Baldwin in 1930 as S-4 locomotive No. 3002.
Source: Wikipedia — Chicago, Burlington and Quincy 4000 (CC BY-SA 4.0)