Travel like the royals of old on our Grand European Cruise, combining Amsterdam to Budapest by Riverboat with Budapest to the Black Sea to create an unforgettable 24-day cruise tour through the heart of Europe ,“ including a 21-day cruise aboard our newest riverboat, ms Treasures. This remarkable voyage from the North Sea to the Black Sea cruises along the Danube, Main and Rhine rivers, taking you through the Netherlands, Germany, Austria, Slovakia, Hungary, Croatia, Serbia, Bulgaria and Romania. Glide past grand cathedrals, medieval monasteries, and historic citadels ,“ as well as through the Main-Danube Canal and the Iron Gate of the Danube. Private, inclusive shore excursions take in many UNESCO World Heritage Sites, and in-depth exploration of cities including Amsterdam, KÃ¶ln, Vienna, Bratislava, Budapest, Belgrade and Bucharest. It’s the ultimate European river cruise.