On one of my recent trips to the Continent I discovered that in Belgium the signposts indicating motorway exits were mostly placed at 1600 m, 800 m and 400 m before the exit.

Looks very much like 1 mile, 1/2 mile and 1/4 mile, doesn't it ?

I'm afraid Belgium has started imperialising... ;-)

Maybe someone in their highways dept. liked the idea of a binary progression?

... or they hired an American civil engineer to design the system

Either way, it makes damn good sense