Steam, Diesel, and Electric.
Union Pacific 4014 spent Labor Day 2021 on display with UP 1989, the Rio Grande heritage unit, at the railroad's Denver Yard; the last stop on the Big Boy's summer excursion before returning to Cheyenne. The Regional Transportation District's A Line runs along the southern edge of the yard, allowing this unique view of the three major types of railroad motive power in the United States - all of which were under their own power!
