Nurmengard is the prison built by the dark wizard Gellert Grindelwald

to hold his opponents. Little is known about the place, as it is only mentioned briefly in Harry Potter and the Deathly Hallows, but it is known to be in Europe, "on an island in a stormy sea". Over the entrance to the prison are the words "For the greater good", Grindelwald's slogan. The prison has several Nazi links; its name, possibly derived from Nuremberg, the scene of many a Nazi rally, the site of a Nazi prison, and the location of the trials of Nazi war criminals. Similar to Grindelwald building the prison, locking up his enemies, and then being imprisoned there himself. Also, the "For the Greater Good" is similar to the Nazi slogan "Arbeit Macht Frei"("Work sets you free"), inscribed over many concentration camps. After his downfall and defeat at the hands of Albus Dumbledore, Grindelwald was imprisoned here himself, until his murder by Lord Voldemort during his search for the Elder Wand.