WW2-era European streets were usually paved with cobblestones. While picturesque, these are a bit of a pain in the butt to model, since you pretty much have to sculpt an entire #%@# bunch of them yourself, or find a textured plastic product (usually not cheap or available locally) to get the effect.
I found this stuff at the local art store for $2. God help me, I think it's scrapbooking paper.
But painted, it makes pretty decent 1:100 scale cobblestones. Go figure.