function bild_grossansicht(URL)
  {
    open("view.php?url="+URL,"gross","width=440,height=430,"
    + "channelmode=no,directories=no,fullscreen=no,location=no,menubar=no,"
    + "resizable=yes,scrollbars=yes,status=no,titlebar=yes,toolbar=no");
  };

function stadtrundgang(URL)
  {
    open(URL,"stadtrundgang","top=50,left=50,height=450,width=520,"
    + "channelmode=no,directories=no,fullscreen=no,location=no,menubar=no,"
    + "resizable=yes,scrollbars=yes,status=no,titlebar=yes,toolbar=no");
  };