CSX (CSXT) Trinity Hoppers - Replaces MC-4212; CSX Transportation was formed on July 1, 1986, by combining the Chessie System and Seaboard System Railroad. The originator of the Seaboard System was the former Seaboard Air Line Railroad, which previously merged Atlantic Coast Line Railroad in 1967, and later Louisville & Nashville Railroad, as well as several smaller subsidiaries such as the Clinchfield Railroad, Atlanta & West Point Railroad, Monon Railroad and the Georgia Railroad. The origin of the Chessie System was the former Chesapeake & Ohio Railway, which had merged with the Baltimore & Ohio Railroad, and Western Maryland Railroad.