Predecessor lines The current AGR is composed of numerous lines built during the late 19th and early 20th centuries, which were gradually consolidated into a system that was purchased by the
St. Louis – San Francisco Railway (the Frisco) and remained under that railroad or its successor's control until 1997, when it was spun off into an independent company.
Pre-1922 The earliest ancestor of the AGR was the Pensacola and Mobile Railroad and Manufacturing Company, which in 1861 constructed of track between
Muscogee, Florida and
Cantonment, Florida. The railroad was not rebuilt until 1877. In 1874, the Pensacola, Mobile & New Orleans Railroad company took control of the Pensacola and Perdido Railroad, which ran west from Pensacola about five miles to a lumber mill at
Millview, Florida on
Perdido Bay. In 1892, the system merged with the Pensacola, Alabama and Tennessee Railroad, which connected the Millview and Muscogee branches. Shortly thereafter, the railroad was renamed the Gulf Ports Terminal Railway. In 1910, the Gulf Ports Terminal Railway was acquired by Southern States Lumber, which operated of track to move lumber from forests in
Baldwin County, Alabama, to its large mill at Muscogee, and on to the port of Pensacola for export. The combined system had a total length of around . In late 2012,
Genesee & Wyoming acquired the railroad as part of its acquisition of RailAmerica. == Fleet ==