Pennsylvania Railroad Class S1 No. 6100, the experimental duplex engine unusually hauling the Liberty Limited during her early service life in 1941.

PRR Class S1 was assigned to power much heavier first class train like the General and the Trail Blazer. Click to enlarge.

(PRR1944, CC BY-SA 4.0 <>, via Wikimedia Commons)



The Liberty Limited was a named train on the Pennsylvania Railroad. It ran from Washington D.C. to Chicago, Illinois, through Baltimore, Harrisburg and Pittsburgh. It began running on September 27, 1925, as a replacement for the Washington–Broadway Limited, which had been introduced in 1923. It originally was scheduled to complete its route in 19 hours.

In June 1938 it became one of the original trains making up the Pennsylvania Railroad's "Fleet of Modernism", using modern streamlined lightweight equipment, along with the General, the Broadway Limited and the Spirit of St. Louis. Beside streamlining, its travel time was reduced to 16 hours 25 mins; 30 mins slower than B&O's premier train the Royal Blue. The train consisted of one lounge Car (Drawing-room, three Double Bedrooms, Buffet), a 14 sections heavyweight Pullman sleeper, a 12-5 and a 10-5 lightweight Pullman sleeper, one dining car, one coach with reclining seat which was regularly assigned, an observation car with two master bedrooms, one double bedroom and a buffet lounge. Prime power was PRR K4s, PRR S1 No. 6100, T1s and diesel engines. Its primary competition were the Baltimore & Ohio's Royal Blue and Capitol Limited.

It last ran on October 27, 1957, after which its equipment was moved to the Chicago–New York General, which also picked up a leg connecting from Harrisburg to Washington, D.C.


Route map of the Liberty Limited. Click to enlarge.

(Via Wikipedia, Creative Commons Attribution-ShareAlike License 3.0)



PRR S1 No. 6100 was seen hauling the Liberty Limited eastbound at New Freedom, PA in April 1941.
PRR S1 6100 6-4-4-6 Duplex Steam Engine or PRR K4s 4-6-2 Steam Engine
Baggage-Lounge Car
3 Double Bedrooms, 1 Drawing Room lounge Car
14 Sections Heavyweight Sleeper
12 Duplex Single room, 5 Double Bedroom Lightweight Sleeper
10 Roomette, 5 Double Bedroom Lightweight Sleeper
Dining Car
Reclining Coach
2 Master Bedroom,1 Double Bedroom Buffet Lounge Observation Car


Portions of a 1952 Pennsylvania Railroad brochure for its train, the Liberty Limited, which traveled between Washington DC and Chicago.

This is the route map of the train. Click to enlarge.

(Pennsylvania Railroad, Public domain, via Wikimedia Commons)



Predecessor: Washington–Broadway Limited
First service: September 27, 1925; 97 years ago
Last service: October 27, 1957
Successor: General
Former operator: Pennsylvania Railroad (1938–1957)
Train numbers: 58 (Chicago to Washington; 59 (Washington to Chicago)


See Also:

Named Passenger Trains A-K

Named Passenger Trains L-Z

PRR S1 Locomotive (Coming soon)