Alton and Sangamon Railroad

Alton Railroad

Chicago and Alton Railroad system as of 1918, including the Toledo, St. Louis and Western Railroad (Clover Leaf) in orange, parent of the Alton until 1921
Reporting mark	A, C&A
Locale	Chicago, Illinois to St. Louis, Missouri and Kansas City, Missouri
Dates of operation	1847 (Alton and Sangamon Railroad)–1947
Successor	Gulf, Mobile and Ohio
Track gauge	4 ft 8 1⁄2 in (1,435 mm) standard gauge
Headquarters	Chicago, Illinois

The Alton Railroad (reporting mark A) was the final name of a railroad linking Chicago to Alton, Illinois, St. Louis, Missouri, and Kansas City, Missouri. Its predecessor, the Chicago and Alton Railroad (reporting mark C&A), was purchased by the Baltimore and Ohio Railroad in 1931 and was controlled until 1942 when the Alton was released to the courts. On May 31, 1947 the Alton Railroad was merged into the Gulf, Mobile and Ohio Railroad. Jacob Bunn had been one of the founding reorganizers of the Chicago & Alton Railroad Company during the 1860s.

Main lines included Chicago to St. Louis and a branch to Kansas City. The former is now part of Union Pacific, with Metra Heritage Corridor commuter rail service north of Joliet (owned by the Canadian National Railway but used by UP). The latter is part of the Kansas City Southern Railway system.

The earliest ancestor to the Alton Railroad was the Alton and Sangamon Railroad, chartered February 27, 1847 in Illinois to connect the Mississippi River town of Alton to the state capital at Springfield in Sangamon County. The line was finished in 1852, and as the Chicago & Mississippi Railroad extended to Bloomington in 1854 and Joliet in 1855. Initially trains ran over the completed Chicago and Rock Island Railroad to Chicago.