Whatever happened in Cologne on Silvesterabend* happened right there in that little triangular space between the cathedral and the train station. The photo is one of many showing the devastation after relentless Allied bombing in 1944. I've been there a couple times, most recently in 2005.
Here's a video taken by a bystander, taken from the steps of the Cathedral bordering the triangle. You can see the facade of the Cathedral's nave briefly when the videographer points his camera skywards to follow a skyrocket.
I watched the whole video purporting to show the mayhem caused by "immigrants." In my opinion, it looks like a typical New Year's Eve in Germany. Germans blow off fireworks on New Years Eve by tradition. I recall being in downtown Berlin for New Years a year or so after The Wall came down. People really did shoot rockets at each other and the cops did nothing. They weren't even standing around: They weren't there. Not having any fireworks myself, I felt "unarmed."
It's really hard to pick out any women in the 12 minute video. That's not surprising, because Silvesterabend fireworks really are a manly thing -- just like fireworks in this country.
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*Silvesterabend means Silvester Eve is December 31st and is named after a 4th century Pope.