It was marked by granite stones (Grenzsteine) with the letters "DDR" carved on the west-facing edge. Around 2,600 distinctive East German concrete "barber pole" (Grenzsäule or Grenzpfähle) markers were installed just behind the border line at intervals of about 500 metres (1,600 ft). A metal coat of arms of East Germany (Staatsemblem) was fixed to the side of the marker facing West Germany.[32]