Passau has the largest Church-Organ in the World: An interior-view of the St. Stephensdome in Passau, showing the largest church-organ in the world. The largest organ in the whole world is the one in the St. Stephensdome in Passau. The 206 organ registers have a total number of 16,105 pipes; the huge bassons have a length of 11,3 m, Each organ can be played separately, but all can be made to sound simultaneously, by a special register board. January 26, 1939. (Photo by Atlantic Photo).