"Is this the road to Spain?"
Translation:Est-ce la route de l'Espagne ?
La route de X is the road linked to X. It takes you from there but also to here, so same thing. I guess the English word "route" might be throwing you off, but the French one, at least here, is really closer to "road", it doesn't have a favoured direction embedded in.
La route vers l'Espagne would be just as correct and possibly a slightly closer translation
La route en Espagne would be either a road within Spain, or less likely the part of a given itinerary that lies within Spain.