Nuremberg, Bavaria’s second city, first pops up in the history books in 1050 as a stronghold of the Franks, and later became the unofficial capital of the Holy Roman Empire. Nowadays the city is a tourist magnet thanks to the beautifully restored old town, Christmas markets and excellent beer.

Originally founded by the Celts and later an important Roman settlement, Regensburg is one of Bavaria’s lesser known gems. Situated on the northernmost bend of the Danube, it’s a friendly and laid back city, with an exceptionally well preserved medieval centre.

The pretty Bavarian town of Passau, situated close to Germany’s border with Austria, enjoys a unique setting at the confluence of three rivers: the Inn, the Ilz and the Danube. The narrow cobbled streets of the handsome old town, the Altstadt, are quite delightful.

Formerly the centre of the Habsburg Empire, Vienna is as grand a European capital as you can imagine, jam packed full of thrusting, bombastic buildings that stand as a reminder of Austria’s glorious imperial heyday.

Budapest is one of Eastern Europe’s most appealing cities, a vibrant and welcoming capital that straddles the Danube. The history of Budapest has been somewhat turbulent, but plenty of beautiful buildings survive, including the imposing Parliament and iconic St Stephen’s Basilica.

Osijek is the capital of Slavonia, a region of eastern Croatia that is hemmed in on three sides by Hungary, Serbia and Bosnia. Tourists are thin on the ground compared to the Dalmatian Coast, yet Osijek is an elegant and cosmopolitan city surrounded by beautiful countryside.

Belgrade has been invaded and occupied dozens of times over the centuries, a fact that's reflected in the mish-mash of architectural styles, from Ottoman and Art Nouveau to grim relics of the communist era. But Belgrade is also a city with real soul, emerging from a difficult recent history as one of Europe’s most exciting capitals.

As the Danube wends its way east, along the border between Serbia and Romania, the river narrows to a dramatic gorge known as the Iron Gates. The river here is flanked by a huge stone carving of Decebalus, the last king of the Dacians and a Romanian national hero.

The riverside town of Vidin is situated in the north west corner of Bulgaria, close to the border with Romania and Serbia. The architectural highlight is the magnificently well preserved Baba Vida fortress, and the town is also home to a mosque, a synagogue and several churches.

The Bulgarian city of Ruse (also written ‘Rousse’) sits on the right bank of the Danube just opposite the Romanian city of Giurgiu, and is one of the country’s most attractive cities. Sometimes known as ‘Little Vienna’, thanks to the plethora of Neo-Baroque and Neo-Rococo architecture, it’s a highlight of any cruise along this stretch of the Danube.