Clues that you may be in France:
The train announcements are exclusively in French.
The street signs are in French.
Everyone you meet primarily speaks French.
The flag of France is prominently displayed in various locations.
The locals take the loss of France's chance at the World Cup *personally*.
Or.
The next morning, when looking over a map and remarking on how *French* the Luxemburg experience has so far been, you happen to notice that you are actually on the *other* side of the French border.
The train announcements are exclusively in French.
The street signs are in French.
Everyone you meet primarily speaks French.
The flag of France is prominently displayed in various locations.
The locals take the loss of France's chance at the World Cup *personally*.
Or.
The next morning, when looking over a map and remarking on how *French* the Luxemburg experience has so far been, you happen to notice that you are actually on the *other* side of the French border.