The town silhouette of Passau is dominated by three crowns: The Maria Hilf Monastery on the mountain of the same name, the cathedral which rises above the old town and the Veste Oberhaus on the Georgsberg. The impressive location of the town on the Danube, the Inn and the Ilz is revealed from the Veste Oberhaus better from any other place. It is located around 100 metres above the city in a perfect place for a castle: from here, the courses of all three rivers, the river crossings and the highway leading to Bohemia can be seen. The castle complex encompasses an area of 65,000 square metres. It is amongst the largest and most powerful castles in Europe.
As the names suggest, there is a significant altitude difference between the Oberhaus and Niederhaus castles: From the Oberhaus, the complex extends down over steep slopes to the spur where the Ilz enters the Danube, on which the Niederhaus stands. The Oberhaus was built from 1219 under prince bishop Ulrich II, the Niederhaus was built in the middle of the 13th century. The two fortresses are connected to one another by a double battlement. Over the centuries, the castle complex has constantly been changed and extended – it is a mirror of the town's history, of Bavarian and European history and the history of fortress construction.
Today, the Niederhaus offers the opportunity to live in the monument: the building is in private ownership and has been divided into thirteen residential units by the owners.
The Veste Oberhaus, on the other hand, houses the OberhausMuseum. The permanent exhibition ranges from the fascination of the Middle Ages to the townscape of Passau to the collection of Hans Wimmer, an important German sculptor of the 20th century. The museum's programme is supplemented by regular special exhibitions.