The GS-1 was a class of conventional 4-8-4 "Northern" type steam locomotive operated by the Southern Pacific Railroad (SP) and its Texas subsidiary the Texas and New Orleans Railroad (T&NO) from 1930 to 1956. A total of fourteen were built by the Baldwin Locomotive Works, numbered 4400 through 4409 by SP and 700 through 703 by T&NO. GS stands for "Golden State" or "General Service."