Railway Post Office service began in 1862 in Illinois with connections to Pony Express. Around the same time Congress proclaimed all railroads as Post Roads and RPO service quickly spread around the country. Until the post WWI years, RPO service was the only practical way to move intercity mail. Cars were equipped with sorting bins and staffed by Post Office personnel. Security was of the utmost concern and the mail crew was typically armed and the doors locked. For most routes the RPO operation didn't require the space afforded by an entire car so the Post Office was partitioned off and the remainder of the car used for baggage and express service. Railroad employees would only have access to the baggage area during normal operation.
Features of these fully assembled and ready to run cars include authentic 19th century styling, interior details and operating knuckle couplers.