|Headquarters||St. Louis, Missouri|
|Dates of operation||1874–1917|
|Successor||Missouri Pacific Railroad|
|Track gauge||4 ft 8+1⁄2 in (1,435 mm) standard gauge|
The St. Louis, Iron Mountain and Southern Railway (St. L., I. M. & S.), commonly known as the Iron Mountain,[a] was an American railway company that operated from 1874 until 1917 when it was merged into the Missouri Pacific Railroad.
The Iron Mountain was initially established to deliver iron ore from Iron Mountain to St. Louis, Missouri. In 1883 the railway was acquired by Jay Gould, becoming part of a 9,547-mile (15,364 km) system. On May 12, 1917, the company was officially merged into the Missouri Pacific Railroad, which in turn was merged into the Union Pacific Railroad in 1982. It was robbed twice, once by the James-Younger Gang, on January 31, 1874, at Gad's Hill, and once by the "One-Time Train Robbery Gang", on November 3, 1893, at Olyphant, Arkansas.
- The railway is famous for giving its name to the Iron Mountain Baby, and the railroad is reported to have paid for the child's education.
- St. Louis, Iron Mountain and Southern Railway 5
- St. Louis Southwestern Railway
- Dardanelle and Russellville Railroad
- Mississippian Railway
- Hipp, Joe Wreford (1996). Legacy of a Robbery on the Iron Mountain Railroad. Little Rock, Arkansas: Renegade Press. ISBN 9781884469091. OL 12153582M.
- Mansker, Dennis (2022). "Albert Mansker: Last of the Arkansas Train Robbers". The Mansker Chronicles. Retrieved September 21, 2022.
- Official website
- Corporate history at the Missouri Pacific Historical Society
- Texas Short Line. St. Louis, Iron Mountain, and Southern Railway Company, 1878 at Cartography Associates