Any details on this huge Iowa derailment?

Back when I was a kid I obtained a book "The Railway" by Schieldrop, printed in the UK with a copyright in 1956. In that book is a pic of an incredible pile-up which is said to be in Iowa but no date or location given. The caption does note it could have been worse, among the 45 derailed cars there were 5 carloads of 16-inch artillery shells which did not detonate.

No particular reason for asking, just curious all these years later which railroad it happened on and what was the cause. From the mess shown in the photo, they are probably STILL cleaning that up!

There appears to be quite a few Milwaukee Road cars involved. It appears that there might be a switch from a siding to a single main track. The general "lay of the land" and all the vegetation make me think of Milwaukee Road's Kansas City main line. Especially around or below Ottumwa.

Just a guess

I do see at least 4 MILW cars there. could be it's on the MILW or maybe some road picked up a block of their cars. I'm not familiar with that territory but your suggestion certainly is plausible.

I'm also curious about the car in the very lower left. My first thought was a caboose but it has no apparent smoke jack. And what are the 6 small vents on the roof?

Last question - is your screen name an "EMD-ization" of your birthday, or a 567-C prime mover from a unit you are familiar with - 26th one built in January 1957?