Bleach Wiki says Western Tokyo with confidence, although not giving a reference.

There's other resources which give the same location.

Thanks! That's what I needed!

I've read somewhere that it's a suburb on the outskirts-ish of Tokyo. Can't remember where, though, I'm so helpful.

probably the data book says.

That seems to be the case. Thanks!

The fictional place is a western ward of Tokyo however it takes its name from a mountain Karakura-san near the very real Hiroshima where Kubo-sensei grew up.

Thanks, that's fantastic info!

If I may clarify the whole West Tokyo thing as well.

First point, there are many Japanese prefecture that share their name with their major city. Osaka, Kyoto and Fukuoka for example. Tokyo used to be like this until 1943 when Tokyo City and Tokyo Prefecture governments were merged to form Tokyo Metropolis.

West Tokyo is basically the part of the old Tokyo Prefecture that wasn't part of Tokyo city. If I remember correctly it extends a couple of hundred kilometres west of the 23 Special Wards (old Tokyo City) so Karakura can potentially be quite some distance from there.

Thanks for the clarification! Very helpful!

Fic research, I loooove it. XD. Yep, part of Tokyo, Karakura is. Don't you love how much you learn when you're writing about your boys?

Haha, yeah! There's an HP comm called hp_britglish where you can go and ask questions about Brit English, slang, way of life, etc. I kinda wish we had one for Bleach, but since we don't, I figured this was the best place to toss out a question. ;)

The Ch. 37 post-chapter doodle shows Karakura's location relative to Yokohama. The Ch. 41 title page has it next to or within "Naruki-shi," but I don't know whether or not that's a real place.