Cheyenne, Wyoming, was an important location on the Union Pacific because of heavy grades to the west over Sherman Hiill. The grades required helper locomotives to get the trains over the hill, and that meant an extensive roundhouse. The tenders stick out of the roundhouse. Rows of wheel sets are lined up in back the the "speeder flats" in the foreground. The frame in the upper left carries electrical power for the turntable. The museum's caption reads: "UP Roundhouse at Cheyenne WY May 1928. note the Wheel sets lined up."