Z had a kid atlas, and we had a globe, but it wasn't until he had been to places and we talked about that that he actually got it. Before that they were just pictures. But "Cardiff is here and Lancaster is here, and that's a lot on this map but a tiny bit on this other map and hardly visible on the globe, and here is Greece where I used to live and here is Canada where our friends live" went in, sometime around three or four. Alex has already been further from Baltimore than Z had from Lancaster -- Lancaster-Cardiff is about a five hour drive -- so she'll have a better idea of scale.