||This article does not cite any sources. (December 2009)
The Oklahoma City – Ada – Atoka Railway (OCAA) was formed from trackage from Oklahoma City to Atoka via Shawnee and Ada, Oklahoma, that was not included in the 1923 reorganization of the Missouri–Kansas–Texas Railroad.
The OCAA was originally owned by interests associated with the Oklahoma Railway, but was sold to the Muskogee Company (which also controlled the Midland Valley Railroad and the Kansas, Oklahoma and Gulf Railway) in 1929. In 1964 the OCAA was sold to the Missouri Pacific Railroad's Texas and Pacific Railway, which briefly operated the property before selling it to the Atchison, Topeka and Santa Fe Railway with which it merged on December 1, 1967.
In 1960 OCAA reported 20 million net ton-miles of revenue freight and no passengers on its 104 miles of road.