When to let your child out alone??

[Rmcni08]

So I was wondering if anyone could give me an outsiders opinion on this?
My son is 9 coming 10 in May, and he is allowed to play in our street with his friends. Only in the street he is not allowed to leave the street.
He walks home from school every day alone which is literally 2 streets away and takes him 3-4 minutes with no main roads to cross.
He is constantly asking to go to the local park with his friends which if I'm honest gives me anxiety the thought of it. It's about 5 minutes away he doesn't have to cross a main road but does have to walk alongside one for the duration of the journey. All his friends from school live about 10 minutes away and have to cross two main roads to get there which they are all allowed to do. He thinks I'm being really unfair by not letting him do everything they are allowed to do like go to the local swimming pool alone, go to the local shopping centre alone all of which I couldn't even imagine letting him do.
I'm really trying to bring myself to compromise and let him go to the park but I genuinely feel sick thinking about it, my OH thinks I'm nuts and thinks he should go.
Please tell me I'm not the only one who over thinks everything like this?
Thanks in advance.

I let both my 8 and 10 year olds go to the park with friends which is about 5 minutes away also no main roads. I depends on how responsable he is and how safe you area is, what is it your are concerned about happening? Also Does he have a phone?

Daughter, now 9, has been able to go to corner shop (about 25m away) since she was 7 and a half. Can now go to post box, Tesco and newsagent about 200m away and across a crossing, go for a jog around the park about 500m away (and a few road crossings) and practice rollerskating in mews behind our house. I'd like her to go to the park with a friend but can't find any friend's parents yet who are up for it, not that I've asked many yet.

The way I look at it is to think backwards - not 'they're too young to...', but 'what will they need to do soon?' ie, in just over 18 months, daughter will have to make her own way to and from secondary school. I want her to be used to going about independently before that, so that doesn't have to be a new experience along with changing schools. Also, I think it's quite good to introduce this experience before she has a mobile device she'll be welded to, so she is used to paying attention when crossing roads.

Yeah he has a phone! I genuinely don't even know what I am concerned about, it just makes me feel super anxious and sick thinking about it! It probably is just me being daft but I honestly am trying to bring myself to let him go. I really don't want him hating me for not allowing him.

He is used to walking home from school everyday and he had been doing this from September and even letting him do that was a massive step for me but he knows as soon as he leaves school he comes straight home. So many of his friends are just allowed to go straight to the park from school and not go home until they are hungry. Even thinking about that give me anxiety

Planning for daughter to walk to school for early choir rehearsal and back from after school classes one day a week from next term when it will be light. It's about a mile, with some crossings. There are some friends who live en route, so I will ask their parents if they might walk together, not sure if they'll go for it.