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.

Situated between France’s Burgundy and Beaujolais regions, Vienne is the gateway to Lyon’s countryside. It is one of the oldest towns in France, with a history that can be traced through its architecture. Among its Roman remains and artifacts, the Roman Temple of Augustus & Livia dates back to the 1st century AD. Its Roman amphitheater, nestled in the hills of Mont Pipet, is one of the best preserved in the nation. Vienne also boasts remarkably preserved medieval buildings and market ruins. Other landmarks include the Abbey of Saint Pierre and the Church of Saint-André-le-Bas.

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.

Located in the heart of Germany's Rheingau region, Rüdesheim is the area's center of winemaking. The famed Drosselgasse, a cobblestone street lined with taverns that pour local vintages and spill music into alleyways, attracts locals and visitors alike. Half-timbered houses, narrow warrens and old inns lend the town a medieval flavor. Castles once provided security for the region, including the 9th-century Brömserburg Castle, the oldest on the Rhine. The Siegfried's Mechanical Music Cabinet museum also houses an impressive collection of self-playing instruments.

Koblenz is a traditional German city, founded more than 2,000 years ago. This former trading settlement rests on a massif of the Middle Rhine Highlands. Its cobblestone streets, wood-beamed houses adorned with flowers, ancient market square and medieval churches recall the fairy-tale Germany of old. At the "German Corner,” a massive equestrian statue of Prince William I observes the lovely riverside scene. The famed Teutonic Knights set up their first base here in 1216. The Romanesque Basilica of St. Castor, Koblenz's oldest building, dates to 836.

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.