Montleek: Robert, is it possible that in Western Europe, the regional lects have been preserved better, while in eastern Europe are preserved worse? There was communism/socialism in Eastern Europe, therefore more tendency not to continue speaking with regional lect.
In Belgium, there are regional lects of Flemish, Dutch, French, Limburgs and German.
Flemish is diverse, though I am not sure if you get to a situation of a different lect in every town.
Dutch is spoken in Belgium, sometimes in forms like Brabants not intelligible to a Dutchman.
Limburgs is actually a separate language spoken in the east. German is spoken in the far south.
The German spoken is a separate language called Ripaurian.
French is spoken as Walloon, actually a separate language
There are probably several languages in Belgian Flemish. There may be two in Limburgs. and there are at least two languages in Walloon. There are probably a few languages inside Belgian Ripaurian. There are at least two languages in Walloon.