From Ohio History Central
Construction of the Cincinnati, Hamilton, and Dayton Railroad (CH & D) began in the Miami Valley in 1846. The railway was completed in 1851 and officially began operation connecting Cincinnati and Hamilton, Ohio. Soon, the railroad stretched onward to Dayton. The line originally ran a total of 59.07 miles.
The construction of the railroad attracted German and Irish migrants who were looking for work. After the railroad was completed, these immigrants stayed in the region and found work in the factories that began to emerge near the railroad and the Miami and Erie Canal.
The CH & D's original purpose was as a commuter line. Professionals and businessman saw the railroad as a way to connect to other cities to conduct business. A number of new communities were built along the rail line, and wealthy people moved out of the city of Cincinnati to live in these communities. Eventually the railroad connected to Toledo and Detroit to the north.
The Cincinnati, Hamilton, and Dayton Railway Company, who owned and operated the CH & D, began to acquire more railroad lines throughout the next 40 years. Beginning in 1863, it operated the Dayton & Michigan RR. Joining the Atlantic and Great Western RR in 1865 gave commuters access to New York and other eastern points. The Ohio and Mississippi RR became part of the CH & D RR linking Cincinnati and St. Louis and western points through Indiana and Illinois. Eventually the CH & D operated additional lines connecting to Indianapolis, Chicago, Richmond, Ironton, Louisville, and Decatur.
By the end of the nineteenth century, the company controlled over 640 miles of track. There were 34 locomotives, 30 passenger cars, and 437 freight cars. The railway included parlors, cafe-coaches, dining cars, baggage, and mail cars. Construction supplies as well as agricultural and petroleum products were transported in freight cars. In 1904, the railroad was not able to handle the volume of passenger and freight business. With this came financial challenges and the Baltimore & Ohio Railroad agreed to purchase the line in 1909. Cincinnati, Hamilton & Dayton Railroad was sold at auction in Dayton and became part of the Baltimore & Ohio.