The sky does appear darker to the naked eye but I'can't see as many stars as in the picture (that's the nice surprise).
The darkest European sky isn't on the continent but on the island of Tenerife, at the El Teide Mount (volcano). I went there in 96 and 97 and remember seing M31 with a blueish spiral halo around its center.

In Belgium, it's the south eastern side (Ardennes) which is the least polluted. In France, near a town called Cahors, there's a so called black triangle (south south east) where there's no light pollution. The mayor of the village at its center has learned this and tries to keep it that way to attract star gazers.

Raoul