I'd like to ask for a source on this. I live in Cologne and I've never heard of such unsafe parks. I do see increased police presence during events like Karnev

I'd like to ask for a source on this. I live in Cologne and I've never heard of such unsafe parks. I do see increased police presence during events like Karneval, but that's not unreasonable with tens of thousands of people drinking and partying on the streets.