PASSAU, an ancient, handsome, and celebrated town of Germany, in Lower Bavaria, with a bishop's see and fort. The houses are well built, and the cathedral is thought to be the finest in all Germany. It is divided into four parts, three of which are fortified; but the other is only a suburb, and has nothing but an old castle in which the bishop generally resides. It is seated at the confluence of the rivers Inn and Ilz with the Danube, in E. Long. 13. 34. N. Lat. 48. 26.