2-8-8-2 locomotives were adopted by a broad spectrum of mountain railroads, including the Norfolk & Western, Southern, Virginian, Great Northern, Clinchfield, Denver & Rio Grande, Reading, Western Maryland, Missouri Pacific, Frisco, and the Duluth, Missabe and Iron Range Railway. On many railroads, the locomotives of the type were the most powerful on the roster. When built, the 2-8-8-2s of the Western Pacific Railroad were among the most powerful steam locomotives in the world and formed the basis for the later 2-8-8-4 "Yellowstone" type engines used by the Duluth, Missabe and Iron Range. The very last compound Mallet locomotives to operate on
2-8-8-2 still used on steel mill lines and other railroads until 1983. Other equivalent classifications are: UIC classification: 1DD1 (also known as German classification and Italian classification) French classification: 140+041 Turkish classification: 45+45 Swiss classification: 4/5+4/5 The first 2-8-8-2 was built in 1909 by Baldwin, who sold two to the Southern Pacific Railroad (classified MC-1), and then three each to the Union Pacific Railroad and UP-owned Oregon Railroad and Navigation Company. Baldwin conceived the type as an expansion of the 2-6-6-2 permitting a greater tractive effort. The next order for the type was from the Southern Pacific; these differed in being