Hex scale in km?

[Tomokatu]

I couldn't find any mention in the manual about the game scale in terms of km per hex.

Why do I want to know?
I'm presently playing with personal preferences set to reveal only two hexes from my units - anything else has to be by air recce.

I just want to know whether I'm assuming knowledge of the forward 25 km or 50 km [&:]or 125km (which would be ridiculous!)
I think this is also important in setting preferences for a pbem.

I know I could measure the distance between two cities in hexes, then refer to a real-world almanack and do the calculations myself but maybe the devs have the info already worked out and immediately to hand? (And I don't want to get into discussion about the extra distance that measurement through a hex vertex gives, as opposed to that through a hexside, either.)

Do other players have opinions on what distance is reasonable during WWII for ground-based intel on distant units?

[Kurak]

As far as I remember it is about 25x25 km.

[Andrew Loveridge]

It is roughly 20 km per hex.

I usually play with 2 hexes revealed.  1 might be a little more realistic, but a lot more challenging! [;)]

[Tomokatu]

Thank you both. I shall imagine 20-25km in future.

Yes, 1 hex visibility certainly MIGHT be more challenging, but even with visibility of 2, I find that the Axis AI attacks my carefully entrenched Poles with "invisible" units - that I can't see during combat resolution and that I never knew were there. It's a bit disconcerting, but then, it's SUPPOSED to be, isn't it.