Quote Originally Posted by Hazir View Post
Colour of the roadsurface very often, lamp posts, lettering on signs, and sometimes a sign telling you you are leaving one country followed by another sign telling you you are entering the other.

Sometimes you can still see where the old border checkpoints were, but most of them have been demolished.
Yes, but if you are on a train? You can only tell by the signs on the next station, really. Well, maybe a bit different building style next to the tracks before that, but that can also occur at other places than the border.

Though if you take a train from the Netherlands to Belgium, it rides on the right track in the Netherlands and on the left track in Belgium. But that's not the case at all borders!