Amsterdam Southeast has metro service which has been in operation for about 30 years. The metro is rather old, but not only that. Graffiti is one of big problem. It makes the metro looks dirty. Cleaners have to work hard from time to time to clean up the graffiti. The new metro is said to come soon but before it comes there must be a solution to refresh the old metro and to combat the graffity. The solution is to invite artists to put their designs as a kind of wallpapers inside the metro. Usually the designs are busy enough so hardly place for graffiti or has strong colours so even graffiti wouldn't be able to attract attention from the passegers. Smart solution!