Many tour customers also enjoy river cruises, which are offered in some of Europe's most popular tour destinations. Below are summaries of the top rivers in Europe.
See a current list of money-saving deals on river cruises, or read on to learn about some of the top sights.
Rhine River -- View rolling vineyards and storybook villages while sailing on one of Europe's most popular rivers. The stretch in Germany known as the Upper Middle Rhine is particularly scenic, home to more than 40 castles.
Danube River -- Flowing from Germany's Black Forest to the Black Sea, the Danube offers a chance to explore Old World cities like Vienna, Bratislava and Budapest.
Douro River -- Learn about Portugal's wine region on a cruise of the Douro. Stop at Porto, a longtime center for the port wine trade, and the 12th-century village of Castelo Rodrigo. The capital city of Lisbon is featured on many itineraries.
Seine River -- These trips typically start in Paris with a day or two of sightseeing, then head west to locales like Richard the Lionheart's stronghold in Les Andelys and Le Havre, where passengers can set out for D-Day landing sites along the beaches of Normandy.
Saone and Rhone rivers -- Itineraries in southern France usually combine these two rivers. During the Saone portion, the ship meanders through the Burgundy region, while the Rhone River runs south through Provence to the Mediterranean coast.
Dutch and Belgian waterways -- These cruises often take place in the spring when fields of colorful tulips are in bloom. Itineraries usually include 80-acre Keukenhof gardens, the windmills of Kinderdijk and the sights of Amsterdam and Antwerp.
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