That cannon looks like the Long Tom that you could see on a hill on Ft. Riley Blvd, between Manhattan and Ft. Riley.
That may be the blvd in the background.
Once you got past Ogden and entered post, no speeding! because the MPs were strict. Buffalo pens on the way to the PX and commissary. Brought back memories, thanks.
Hey...I was an MP on Riley!
The Ogden cops were worse, lol
I think this is it: https://www.roadsideamerica.com/story/2102
“The Atomic Cannon, an M65-280mm, can throw a shell 20 miles, which would place ground zero southwest and just shy of Abilene (home of the Eisenhower Museum).”