> my personal litmus test is if you'd let your 13 year kid explore Manhattan alone during the day
My parents let me (14) and my brother (9) explore central Paris on our own when my Dad was working at the Paris air show for the RAF. No problems at all even though this was just after the student protests in the 60s, and so things were a little tense.
I think Manhattan would be OK too, though I've only been there as an adjust. Certainly, you see kids running around London.
13??? I’m shocked that it’s even a question. Of course a 13 year old should be allowed to do that.
s/adjust/adult/
London and the bits of Pars I have seen are pleasant places to work around. London does have its bad areas, as do other cities. Small towns in the UK are fine, as is most public transport. Parents have got more protective but I still see plenty out by themselves where I live.