Hi Dirtyred, it's a hardy geranium, sorry I can't tell you which variety but someone will, Derek.

Thank you Derek!

Looks like a hardy geranium to me Dt, "Johnsons blue" I think.

That's brilliant, thank you Stroller! :)

I think its Geranium Magnificum. The leaves aren't right for Johnsons Blue.

I'd go G magnificum too

I first thought G. magnificum; But it doesn't look right.
The veins are much more prominent in the pics above.

My second thought is - Geranium bohemicum 'Orchid Blue'

Thank you all so much - its been in the garden since before I moved in, always loved it, wonderful to know what it is!

Probably G. magnificum then as it's one of the established species and has been around longer than Orchid Blue which is short lived (although it seeds itself about). Derek, you're right about the colour, but I think that's just perhaps a shady site having an effect.

Thanks Worthy - that would seem to confirm it as G. Magnificum to me then as the plant has been there 10 years or more. Again thanks to all for helping me put a name to it :)