404. That’s an error.

The requested URL /bookmarks/mark?op=edit&output=popup&bkmk=http%3A%2F%2Fwww.ddr-museum.de%2Fde%2Fblog%2Fthema-ddr%2Ferst-bruecke-der-einheit-dann-agentenbruecke-die-glienicker-bruecke-in-potsdam&title=Erst+Br%C3%BCcke+der+Einheit%2C+dann+Agentenbr%C3%BCcke+%E2%80%93+die+Glienicker+Br%C3%BCcke+in+Potsdam was not found on this server. That’s all we know.