They have been around for a while, but I’ve never seen them documented anywhere, and so I present you : Suske en Wiske traffic signs. The most popular heroes in Flemish comics do their best to change attitudes towards behavior in traffic, with messages as “only cross the road at a guarded crossing” or “don’t speed in town centres”.
I’m not sure whether these signs are iconic enough to get their message across in the split second a driver has to interpret them, but at least they bring some color in the streets. Now, if only they had chosen a proper typeface, instead of that infernally childish Comic Sans…
