Avignon’s narrow streets are lined with churches and remarkable medieval buildings. This “City of Popes” was the papal seat for 70 years during the 14th century after the sitting pope abandoned Rome and fled here. The massive church-fortress Palais des Papes, or Palace of the Popes, was the center of the Christian world during that controversial period. It remains a work of Gothic splendor. Another of Avignon’s notable structures reaches into the Rhône, the ruins of the Pont d’Avignon. The 12th-century bridge, immortalized in folk song and dance, once spanned the river.

In the last days of the Roman Empire, Arles was the capital of Roman Gaul and boasts many Gallo-Roman ruins including Les Arènes; this ancient amphitheater seats 20,000 and is still used today for bullfights and plays. The town has an energetic feel, attracting farmers from the countryside to the frequent and famous Provençal market. It also enjoys a rich artistic heritage; the Mediterranean sunlight here inspired legendary Impressionist Vincent van Gogh to paint a number of works. Many of Arles’s sights are immortalized in his paintings.

When the Catholic Church acquired Avignon during the 1300s, it quickly transformed the quiet riverside village into a major religious and cultural center. Evidence of the makeover is everywhere. In addition to the enormous palace, the church constructed a wall around Avignon and provided mansion-like residences to its cardinals. Avignon Cathedral was dwarfed by its neighbor, the Palace of the Popes. Centuries after the papacy returned to Rome, the Vatican called for a gilded statue of Mary to be placed atop the cathedral; her golden gaze still welcomes visitors today.

The sleepy town of Viviers was founded during the 5th century. This former Roman settlement became a bishop’s seat, and conflicts during ensuing centuries required the town to be fortified. With the Renaissance came a more stable period of wealth that allowed many new houses to be built, including a fine example of the era that still stands, the Maison des Chevaliers. Some buildings date back to the Middle Ages, and time seems to stand still along the cobblestone streets of its Old Town, dominated by the 12th-century St. Vincent Cathedral with its beautiful windows.

Tournon lies secluded between the river and the vineyard-blanketed granite slopes that nurture fine vintages. An ancient castle, built snugly into a rock, overlooks the riverside setting. A settlement has perched on this hill since Celtic times, but the stunning views from its overlook have never changed. The name of its neighboring wine-producing region, Tain-l’Hermitage, comes from the hermit who planted vines here after returning from the Crusades. Today, his vines are awash in sunshine and produce a port-like wine and some stellar whites.

Lyon straddles the Rhône and Saône Rivers. After Paris, it is considered the country's most significant cultural center. Amid a cityscape of red-roofed buildings, tree-lined boulevards and riverside promenades, the cobblestone streets of Old Lyon host a rich collection of Renaissance architecture and intimate traboules, unique passageways through buildings that connect adjacent streets, all of it overlooked by the grand basilica atop Fourvière Hill. The city also boasts a wealth of outstanding museums, cultural treasures and excellent Lyonnaise eateries.

Lyon is known as the food capital of France. It is not uncommon for well-heeled Parisians to travel to Lyon for dinner. The city is surrounded by towns and villages that produce excellent fresh produce, and gastronomic outlets are plentiful here. The great chefs of Lyon enjoy celebrity status, whether they prepare classic recipes the traditional way or elevate them with their own signature touches. Their delicious meals may be paired with a glass of light, fruity Beaujolais from the north or a bold Rhône red from the south.

Located where Switzerland, Germany and France meet, Basel reflects a fascinating blend of traditions. The city straddles the Rhine at the river's farthest navigable point, and an alluring cluster of old-town buildings huddles along the riverbank. Around Market Square, guild houses recall Gothic, Renaissance and baroque splendor; the red-sandstone Rathaus, or Town Hall, is the centerpiece. More than 40 museums of art and culture lend modern polish to its history-rich streets. And there is no more refined way to sample it all than over cheese fondue or croissants.

Breisach is a gateway to the fabled Black Forest region, built on a basalt rock outcropping in the Rhine plain. It is located in one of the warmest parts of Germany, across the river from French Alsace, famous for its wine growing. But Breisach, too, can boast about its wine: it is home to Europe’s largest cellars, with a storage capacity of more than 160 million liters. The most prominent landmark of Breisach is the Romanesque-Gothic St. Stephen’s Cathedral, built between the 12th and 13th centuries. Its two towers are visible from throughout the city and from the Rhine.

The largest port on the Upper Rhine, Strasbourg is the cultural center of France's Alsace region. Thanks to its location at the border of France and Germany, it boasts a convivial mix of cultural influences. The well-preserved old town is enclosed on all sides by the little Ill River, with sites so compact that it is easy to explore the "island” on foot. And there is plenty to explore: cobblestone streets lined with wooden houses and intersected by picturesque canals. Indulging in Alsatian café culture is central to any visit here; enjoy coffee and cake amid lovely half-timbered houses.

The quiet German town of Speyer lies on the west bank of the Rhine. The city features a Romanesque imperial cathedral, burial place of eight emperors including some of the most famous Holy Roman Emperors. Speyer was once a major Celtic center that traded hands several times between the Romans and the Huns. The term Protestant originated here at the Diet of Speyer in 1529, when 14 free cities of Germany and six Lutheran princes protested the Edict of Worms that had banned the writings of Martin Luther and labeled him a heretic and enemy of the state.

The Rhine River flows through one of Germany’s most scenic regions. As you sail its most picturesque stretch, the UNESCO World Heritage Site of the Middle Rhine, you will pass vineyard-blanketed hills whose steep slopes require vintners to pick grapes by hand, keeping a centuries-old tradition alive. Splendid castles line the banks, all of which have stories to share, and the Lorelei Rock presides at a dramatic curve in the river. This infamous river maiden mesmerized sailors with her song and lured them to their demise at her feet.

Cologne reveals its Roman heritage in its city layout and the ancient ruins that lie scattered through the town. Cologne's modern plazas and Hohe Strasse host welcoming shops, enticing restaurants and cologne boutiques. Of note is the city's 13th-century cathedral, a stunning example of Gothic artistry and a UNESCO World Heritage Site. Having survived Allied bombs during World War II, the cathedral's imposing twin spires are visible for miles and its stained glass windows fill the interior with brilliant colored light. Its steps lead to a platform with astounding views.

Sail the bucolic waters of the Rhine, deep into the Rhine–Meuse–Scheldt Delta, as classic Dutch landscapes unfurl all around. Flat farmland, charming windmills and svelte poplar trees line the shores, and vast tracts of land stretch in all directions, growing all manner of bounty, from tomatoes to tulips. Gaze upon Friesian cows and tidy villages with their neatly laid farmhouses and marvel at how much of this land was reclaimed from the sea, with the aid of traditional windmills and the construction of dikes.

Bid farewell to your fellow guests and journey home. Or spend more time exploring, perhaps joining one of our extensions.