The Chesapeake and Ohio Railway (reporting marks C&O, CO) was a Class I railroad formed in 1869 in Virginia from several smaller Virginia railroads begun in the 19th century. In 1963, the C&O helped start the modern merger era by "affiliating" with the Baltimore & Ohio. The two lines' services, personnel, motive power and rolling stock, and facilities were gradually integrated. The C&O, B&O and Western Maryland Railway became Chessie System, formally adopting a name that had been used colloquially for the C&O itself, after the mascot kitten used in ads since 1933.
Chessie System then merged with Seaboard System Railroad (itself a combination of great railroads of the Southeast including Seaboard Air Line Railroad, Atlantic Coast Line Railroad, Louisville and Nashville Railroad, Clinchfield Railroad and others), to form a new mega-railroad: CSX Transportation. Western Maryland was merged into B&O on May 1, 1983. B&O was merged into C&O on April 30, 1987, and C&O was merged into CSX Transportation on Aug. 31, 1987. After acquiring 42% of Conrail in 1999, CSX became one of four major railroad systems left in the country.
Exact timeline not yet determined.
Known to be in use in 1934-1946:
Known to be in use in 1949-1952:
Known to be in use in 1951-1957:
Known to be in use in 1962 (special use):
Known to be in use in 1964:
Known to be in use in 1966:
Known to be in use in 1968 (special use):
Broadway Limited Imports offers a C&O T1 2-10-4: