The first sentence:
nuevos zapatos por España
Doesn't really make sense. I mean someone that speaks Spanish would not understand what you mean. In that sentence when i read it, that "por" feels like "for" in the sentence "for the cause".
Although in some places people would understand "tenis" as Alfredo said. It is not really that used in many countries. I would say "zapatillas", I think most people would understand that, at least in the countries I have been.
As I said I think it depends a lot of what country you come from.
So in the picture you want to post, i would say something like:
"Mis nuevas zapatillas para la maratón en España".
You could say too
"Mis zapatatillas nuevas para correr el maratón en España"
The answer by Alfredo, is correct too. I think is a more formal way of saying what you want to say.
Your original sentence
nuevos zapatos para España
It is good too, but just replace zapatos with "tenis" or "zapatillas".