Passau sits at the point where three rivers meet, in the far east of Bavaria, close to the Austrian border: the Danube, which is a cold greenish-blue here, the Inn, which arrives milky green from the Alps, and the Ilz, a small, dark river that stains the water black from the peat of the Bavarian Forest. On a still day you can see all three colours running side by side at the tip of the old town, which is why people call it the City of Three Rivers, and sometimes the Bavarian Venice.
The Romans knew the site well, since it stood on the northern frontier of the empire, along the Danube limes. The fort of Batavis, on the old town hill, guarded the crossing, and another fort, Boiotro, stood across the Inn. Fragments of the walls and finds from the forts are held in local museums, and the Roman past lies under the later city, which grew rich on the salt trade, brought down the rivers and traded here, and as the seat of a powerful prince-bishop. In the baroque old town, the cathedral of Saint Stephen has the largest cathedral organ in the world, with nearly eighteen thousand pipes, and organ concerts are held at midday in summer.
The old town is a narrow peninsula of steep lanes and pastel houses, with arcades and small squares, and the town hall tower looks over the Danube, with flood marks on its wall showing the levels of past floods. The riverside paths are part of the long Danube cycle route, and boat trips leave from the quays. A walk up to the Veste Oberhaus, the fortress above the Danube, rewards you with a view of the confluence.
For riders, Passau is the starting point of some excellent roads. The Danube valley above, in Austria, forms great loops, such as the famous Schlögener Schlinge, a few dozen kilometres upstream, and the hills of the Bavarian Forest to the north have winding roads through spruce woods. Across the border, the Czech village of Holašovice, a perfectly preserved South Bohemian baroque village, is on the ride. Traffic in town is dense and parking limited, so use a car park on the edge and walk in.
Passau has fuel stations on the main roads and plenty of cafes and restaurants. Try a Bavarian pork roast with dumplings, or a pretzel and a mug of the local wheat beer, in a beer garden by the river.