The UP is the largest railroad in the United States and traces its history back to the 1860's. Along with a long standing and rich heritage, the UP maintains a fleet of historic locomotives and rolling stock for use at public day events and special business trips; these "excursion trips" are an opportunity for the railroad to show actual operational railroad history to new generations of railroad fans both young and old, pairing majestic steam locomotives such as the FEF-3 #844 (the "living legend") with modern diesels such as UP's fleet of Heritage SD70ACe locomotives as the general public is invited to explore (and even ride!) UP's preserved passenger equipment. Many of the UP's older heritage cars have been repurposed specially for these excursion trains, such as the 1962 vintage Baggage car "Promontory" which has been rebuilt into a traveling museum exhibit filled with interactive exhibits and memorabilia from the UP's past. Even more drastically modified is a special ex-Baggage Dormitory car, gutted and rebuilt to house a diesel generator as a power car to provide head end electrical power to excursion trains pulled by Union Pacific's steam locomotives. These cars and more join well-kept vintage Pullman and ACF-built luxury passenger cars to help preserve the historic golden era of US Passenger trains as the UP continues to operate and support railroad exhibitions in the modern era.