Christmastime on the Danube (Eastbound)

Nuremberg commands the imagination on two levels: as the glittering medieval city where Holy Roman Emperors held court, Albrecht Dürer was born, and craftsmen produced the first pocket watch — and as the site of the 20th century's darkest chapter, where Nazi rallies and subsequent war crimes trials left permanent marks on European history and conscience. The Kaiserburg castle crowning the hill above the perfectly preserved old town offers sweeping views of a cityscape that, despite wartime bombing, remains one of Germany's most beautiful. The Documentation Centre on the former Nazi Rally Grounds is essential, sobering history; the Christmas Market on the Hauptmarkt, held since 1628, is among Europe's finest. Visit May through October or December.

Regensburg, Bavaria's medieval masterpiece on the Danube, is one of Central Europe's most intact ancient cities — its Roman origins visible in the Porta Praetoria stone gate, its medieval prosperity celebrated in the soaring twin towers of St. Peter's Cathedral and the twelfth-century Stone Bridge. UNESCO World Heritage status acknowledges a skyline dotted with patrician towers, while the famous Historische Wurstküchl, Germany's oldest operating sausage kitchen, has been serving spit-grilled bratwurst since the 1140s. The surrounding hills produce excellent Bavarian whites. May through September offers the most convivial riverbank atmosphere.

Passau occupies one of Central Europe's most dramatic natural stages — a narrow peninsula at the confluence of three rivers, the Danube, Inn, and Ilz, where the old town's baroque spires and shuttered merchants' houses crowd the very tip of the land between the waters. St. Stephen's Cathedral houses the world's largest church organ, a 17,974-pipe instrument whose daily concerts fill the nave with a sound that seems architectural in its density. The Veste Oberhaus fortress above the city commands panoramic views across three countries on clear days. Passau is a classic Danube river cruise departure point; spring and early autumn, when the river runs high and the light turns golden, are the finest seasons.

Melk Abbey is among the most theatrical expressions of Baroque ambition in all of Europe — a gilded monastery perched on a granite outcrop above the Danube, its domed church and frescoed library presiding over the Wachau Valley with serene authority since Benedictine monks replaced the Babenberg fortress in 1089. Umberto Eco immortalised it as the inspiration for his labyrinthine monastery in "The Name of the Rose," and the library's 100,000 medieval manuscripts remain one of the continent's supreme collections. After the abbey, stroll down to the historic market town and sample the valley's celebrated Grüner Veltliner wines. The Wachau is at its most bewitching in April and October.

The port of Vienna is a cultural gem along the Danube River, famous for its stunning architecture, rich history, and vibrant culinary scene. Must-do experiences include sampling authentic Wiener Schnitzel and visiting the picturesque village of Dürnstein. The best season to visit is spring or early fall, when the city's gardens bloom and outdoor activities abound.

The port of Vienna is a cultural gem along the Danube River, famous for its stunning architecture, rich history, and vibrant culinary scene. Must-do experiences include sampling authentic Wiener Schnitzel and visiting the picturesque village of Dürnstein. The best season to visit is spring or early fall, when the city's gardens bloom and outdoor activities abound.