Mail Sorting Car | B&O Railroad Museum

Location: Roundhouse, Bay 20

Originally built as the Maryland & Pennsylvania (Ma & Pa) No. 42 in 1906, this freight car was renamed the Ma & Pa No. 35 in 1942 when it was converted to a Railway Post Office (RPO) facilty for mail to be sorted and transported while traveling between York, PA and Baltimore, MD. The front half of the car was primarily responsible for carrying baggage and other freight along the railways, and eventually the Ma & Pa line became known as the “Milky Way” due to the large quantities of milk that it transported from local farms to the cities. While mail cars such as this reached their peak around 1913, the advent of the automobile led to a sharp decline in their use, and this car was retired from use in 1971.

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More Exhibitions

The Underground Railroad: Freedom Seekers on the B&O Railroad

The Underground Railroad: Freedom Seekers on the B&O Railroad examines the role of the physical railroad in the Underground Railroad network and gives an intimate look at the lives and journeys of 27 individuals who sought freedom from slavery along the B&O.

Bank of America Model Train Gallery

The Bank of America Model Train Gallery features an exquisitely detailed HO Scale model train layout of Baltimore City as well as an exhibit visually exploring the various North American model train scales (or gauges).

The Roundhouse: The First Century of American Railroading

The historic B&O Roundhouse, built in 1884, features the most comprehensive collection of early American locomotives and rolling stock in the world. Known as the Cathedral of Railroading, this grand hall showcases some of the greatest locomotives of the first 100 years of railroading.

The First American Locomotives: Fair of the Iron Horse

This section of the Roundhouse explores the very first locomotives, passenger cars, and freight cars used by America’s first railroad, the Baltimore and Ohio Railroad. These pieces were used in the Fair of the Iron Horse celebration commemorating the 100th anniversary of the B&O in 1927.

Civil War: The War Came by Train

As a relatively new technology, the Civil War was the first war in the world to use trains. This exhibition in the Roundhouse displays how the B&O joined the Union war effort, featuring one of the only remaining locomotives to have seen combat in the Civil War, the Memnon.

North Car Shop: 20th Century American Railroading

The North Car Shop is the oldest surviving railroad manufacturing building in the world. Inside, explore a survey of 20th century locomotives and rail cars, from the last examples of steam to some the earliest historic diesels.

Connectivity: Art at the Intersection of Rail, Community, and Identity

The Baltimore-based artists selected for this exhibit were asked to reflect on the concept of connectivity as it relates to the railroad, our community, and our own identities.

Smithsonian Model Train Collection

This hall features a variety of exquisite model trains from the Smithsonian’s collection covering almost 200 years of railroading history.

Jim Crow Segregated Car

This car is preserved its Jim Crow era segregated design. Built for the Chesapeake and Ohio Railroad, it served predominately in Southern states. Visitors can enter the car to view the different sections and learn about the perseverance of African American activists who worked to end segregated rail travel.

Mail Sorting Car

By the 1930s, mail was a primary cargo for the railroad industry. Visitors can explore the inside of a mail car and view a mail sorting area that acted like a mobile post office.

Founding the B&O Railroad

The B&O Railroad Museum’s site is the birthplace of American Railroad. This exhibition shares the story of the founding of the B&O Railroad in 1827.

World War II Troop Car

During World War II, the railroads were responsible for moving soldiers and materials for the war effort, while at the same time continuing their passenger services. Explore how the government used railroads in the war effort by exploring the inside of this troop sleeper car.

The Dynamometer Car

The dynamometer car was an important part of measuring a locomotive’s performance in several categories, such as speed and tractive effort during a specific type of weather. Explore this fascinating meter on wheels and the accompanying crew quarters.

HO Scale Model Layout: Early History of the B&O

Don’t miss our train car sized HO scale model train layout. This moving exhibit depicts the early mission of the B&O Railroad – to reach out from Baltimore toward the Ohio River through the Appalachian Mountains.

Dining on the B&O: The China Collection

The interior of this historic dining car boasts an impressive display of B&O Railroad dining china and silver, used to serve food on its premier routes. Learn how B&O staff and Pullman Porters provided a truly “fine dining” experience in their dining cars.

Cool Runnings on the Railroad: The American Refrigeration Car

Enter our modern refrigerated car, once used to haul frozen McDonalds fries around the country, and explore the critical role railroads play in shipping American freight.

About Time: The Standardization of Time

Railroads played a critical role in the standardization of time in this country, as well as the development and need for precise time keeping instruments. This gallery features clocks and pocket watches from the museum’s collection and explores the history of time and the railroads.

Train Garden: The B&O Railroad Museum’s Open Storage

Can’t get enough trains? Explore our train garden – the museum’s open air storage around the parking lot featuring some truly historic locomotives, freight and passenger cars, as well as rail maintenance equipment.