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This shot was taken from the US 66 bridge late in the afternoon on May 27, 1987. If I remember correctly, the highway bridge was built in 1947 and US 66 then used a more southerly route between Flagstaff and Winona. Train 508 had engines 5328, 5804, and 5959.
Notice that it is more difficult to get good shots of trains to the west of the bridge in the late afternoon. Disk 69