The longest river cruise in the world is the Viking Grand European Tour, which travels along the the Danube, Main, and Rhine Rivers and is operated by Viking River Cruises. The cruise begins in Amsterdam, Netherlands and ends in Budapest, Hungary, and covers a distance of 1545 miles (2487 km).
The specialty of this cruise is that it takes you through the heart of Europe, visiting several countries and cities, including Germany, Austria, Slovakia, and Hungary. It offers a great way to experience the culture, history, and natural beauty of the region. Passengers can enjoy guided tours of iconic landmarks such as the Brandenburg Gate in Berlin, the Hofburg Palace in Vienna, and the Gothic St. Stephen's Cathedral in Passau. They also have the opportunity to explore charming towns and villages along the way. The cruise also includes included shore excursions, meals and on-board entertainment, making this an all-inclusive and hassle-free way to explore the most iconic destinations in Europe.