Soo Line 1003 is a class "L-1" 2-8-2 "Mikado" type steam locomotive built by the American Locomotive Company (ALCO) in March 1913 as a member of the Minneapolis, St. Paul and Sault Ste. Marie Railroad L-1 class. It was retired from regular revenue service in August 1959 and restored to operating condition on October 27, 1996. Today, it is occasionally operated on the major railroads of the American Upper Midwest.

The American Locomotive Company was an American manufacturer that operated from 1901 to 1969, initially specializing in the production of locomotives but later diversifying and fabricating at various times diesel generators, automobiles, steel, tanks, munitions, oil-production equipment, as well as heat exchangers for nuclear power plants.