I have MudMap on my iPhone5 and this satisfies my GPS/4WDing needs in Westralia.

I'm about to go to Spain and would really like to use the app for navigating our way around (rental car, not 4WDing) - is there anywhere I can download free road maps of Spain for this purpose?

I really know nothing of GPS other than loading this app and seeing where I am!

Any help appreciated, Sam