The class was known for its striking art deco shell, its ability to pull trains at up to 100 mph, and its long operating career of almost 50 years.

The GG1 entered service with the PRR in 1935 and later ran on successor railroads Penn Central, Conrail, and Amtrak.

The control cabs were near the center of the locomotive on each side of the main oil-cooled transformer and oil-fired train-heating boiler.

A pantograph on each end of the locomotive body was used to collect the 11,000 V, 25 Hz alternating current (AC) from the overhead catenary wires.

"[9] Beginning in the late 1910s, the PRR received the FF1, but decided that it was too slow for passenger trains; it was relegated to heavy freight service.

The mechanical design of the GG1 was based largely on the EP3, which the PRR had borrowed from the New York, New Haven & Hartford Railroad to compare it to the P5a.

[10] In 1933, the PRR decided to replace its P5a locomotives; it asked General Electric and Westinghouse to design prototype locomotives with a lighter axle load and more power than the P5a, a top speed of at least 100 miles per hour (160 km/h), a streamlined body design, and a single (central) control cab.

[13] PRR chose the GG1 because the R1's rigid wheelbase prevented it from negotiating sharp curves and some railroad switches.

[18] They initially retained their train-heating steam generator, and were recalled to passenger service for holiday-season mail trains[18] and 'Passenger Extras' such as those run for the annual Army–Navy football game in Philadelphia.

[citation needed] On June 8, 1968, two Penn Central GG1s hauled Robert F. Kennedy's funeral train from New York Penn Station to Washington, D.C.[20] The first designer for the GG1 project was industrial designer Donald Roscoe Dohner, who produced initial scale-styling models, although the completed prototype looked somewhat different.

[21][22] At some point, PRR hired famed industrial designer Raymond Loewy to "enhance the GG1's aesthetics.

[24] On September 6, 1943, the Congressional Limited crashed at Frankford Junction, in the Kensington section of Philadelphia, Pennsylvania.

The journal box seized and an axle snapped, catching the underside of the truck and catapulting the car upwards.

A signalman, hearing the horn and noting the speed of the 4876, phoned ahead to the station master's office.

[31] The only major electro-mechanical breakdown of the GG1 was caused by a February 1958 blizzard that swept across the northeastern United States[32] and put nearly half of the GG1s out of commission.

Exceptionally fine snow, caused by the extreme low temperatures, passed through the traction motors' air filters and into the electrical components.

[36] An E60 derailed during testing at 102-mile-per-hour (164 km/h), forcing an investigation (the E60 used the same trucks as the P30CH diesel then in service with Amtrak) that delayed acceptance.

A replacement was finally found after Amtrak imported and tested two lightweight European locomotives: X995, an Rc4a built by ASEA of Sweden, and X996, a French design.

[citation needed] During the mid-1930s, many railroads streamlined locomotives and passenger cars to convey a fashionable sense of speed.

"[43] PRR-painted GG1s appear in the films Broadway Limited in 1941, The Clock in 1945, Blast of Silence in 1961, the 1962 version of The Manchurian Candidate, and Avalon in 1990.

[50] PRR GG1 4821 appears briefly in the 1952 film The Greatest Show on Earth, hauling the Ringling Bros. Barnum & Bailey Circus into Philadelphia's Greenwich Yard, as the movie's director Cecil B. DeMille narrates the scene of its arrival.

A GG1 and the Congressional were featured on a postage stamp as part of the United States Postal Service's All Aboard!

A GG1 in a fictional Soviet color scheme appears as an environmental prop in the 2023 first-person-shooter Atomic Heart.