Switzerland is synonymous to efficiency and the Alps are swept clean first thing every morning. It's therefore disturbing (and simultanously comforting) that different kinds of roadsigns are allowed to coexist.
One type features heaps which are round and slightly undulating. Another type shows more irregular heaps and there's also a make with more edgy heaps.
On all signs the worker transfers earth from one heap to the other. His labour won't do any good to the country's cleanness and in some other countries the meaningless activity would be considered torture — except when he's a landscape garden architect.