Nickel Plate Road (NKP) No. 172 is a Class L1b a type of 4-6-4 "Hudson" steam locomotive. It was built in 1927 by Alco for the Nickel Plate Road.
This special Hudson was used to haul heavy passenger trains and freight trains on the Nickel Plate Road railroad.
No. 172 remained in service until 1947 when it was retired from service and it was cut up for scrap.