Eternal Danube with Serbia, Croatia & Iron Gates

Vienna is a city that defies simple description. Over the centuries, it has been an imperial city, seat of the Holy Roman Empire, capital of the Austro-Hungarian Empire, and capital of sovereign Austria. Today, Vienna retains the grand Baroque architecture, historic style, and Lebenskunst (art of living) that attracted famous composers like Mozart and Strauss. It's a wonderland of lavish palaces and cathedrals, world-class museums and music venues, atmospheric coffee houses, and romantic fiakers (horse-drawn carriages) clip-clopping past it all.

Capital of Hungary from the 10th to mid-13th centuries, the royal city of Esztergom is where St. Stephen, Hungary's first king, was crowned. Esztergom Basilica, the country's largest church and seat of the Catholic Church in Hungary, houses the nation's largest ecclesiastical collection, while Esztergom Castle sits majestically on a cliff overlooking the Danube. Meanwhile, the city's medieval center is walled by Baroque, Rococo, and Neoclassical buildings and features a lively market square whose houses were occuped by rich merchants in the 17th century.

Visegrád is a small Hungarian castle town, just north of Budapest on the right bank of the Danube. In 1325, King Charles I of Hungary named Visegrád the country's royal seat; however, that honor transferred to Buda around 1405. It is known for its beautiful medieval fortress (Upper Castle); remains of an important Roman fort built in the 4th century; Lower Castle with the hexagonal Solomon Tower; and the 14th-century Royal Palace with its Gothic cloister. The town is also popular for its thermal spas and excellent Hungarian cuisine, including hearty stews, grilled meats, and superb local wines.

One of the most beautiful cities in the world, the wonders of Budapest rise up along both banks of the Danube in a truly impressive way. Along with Heroes' Square with its Tomb of the Unknown Soldier, awe-inspiring Hungarian Parliament Building, and the lavish Castle District with photogenic Fishermen's Bastion, the city is home to a captivating Jewish district and the second-largest synagogue in the world, an intricate underground cave system, and some of Europe's most famous thermal baths.

The port town of Mohács holds an interesting distinction. Battles here in 1526 and 1687 marked both the beginning and the end of Ottoman rule over Hungary. The town's origin dates back much earlier than that, though, as a Roman camp on the banks of the Danube. Today, one of Mohács most colorful traditions is the annual Busójárás Carnival, a lively display of music and dancing, cowbells and clappers, wooden pitchforks and puppets, food and drink, mask-carving and bonfires, all to chase winter away.

Born on the banks of the Danube when Serbian merchants formed a colony across from Petrovaradin Fortress in 1694, Novi Sad has evolved into a haven of Serbian culture, earning it the nickname of "Serbian Athens". Home to a soaring cathedral, Bishop's Palace, theater, Jewish Synagogue, and more, Serbia's second-largest city is also a bustling university town that was named Youth Capital of Europe in 2019 and a European Capital of Culture in 2022.

Situated along the famed Orient Express, where the Danube and Sava Rivers meet is Belgrade, one of the Danube's four riverside capitals. This is one of the world's oldest continuously inhabited cities—a place sieged, razed, and bombed by outsiders trying to control it. Today, the one-time capital of Yugoslavia is a thriving hub of government, finance, and urban renewal of many former communist-era districts. It is home to the Church of Saint Sava, one of the largest Orthodox churches; the famous Nikola Tesla Museum; Kalemegdan Fortress; and more.

A stronghold during Roman and Byzantine times, the eastern Serbian village of Golubac is surrounded by fascinating archaeological sites and imposing Golubac Fortress, gateway to Đerdap National Park and the Iron Gates gorges. Although the medieval fort had 10 defensive towers, it was attacked repeatedly over the centuries, changing hands between the Turks, Bulgarians, Hungarians, Serbs, and Austrians. Today, Golubac Fortress is part of Serbia's declared Immovable Cultural Heritage of Exceptional Importance, attracting thousands of visitors from around the world each year, while Golubac village is a popular destination for fishing, hiking, and sailing.

Located in the Veliki Kazan gorge, a section of the famed Iron Gates in Đerdap National Park, is Donji Milanovac, whose peaceful Serbian beauty is breathtaking. So much so, in fact, that filmmakers flock here, earning it the nickname of "Serbian Hollywood". Nearby, archaeologists have unearthed sculptures, weapons, and tools up to 9,000 years old that bear witness to an advanced Stone Age civilization—Lepenski Vir, one of the oldest settlements in Europe.

Sitting on the right bank of the Danube, the site of the eastern Serbian town of Kladovo has been inhabited since the Early Bronze Age. Today, Kladovo is popular for its beaches, wine trails, cuisine, and adventure activities, but the allure of the ancient past remains as strong as ever. This is where Roman Emperor Trajan built his legendary bridge across the Danube, and where the Romans also constructed Diana Fortress in the 1st century. Part of a vast defensive system along the empire’s border, Diana included a military camp, watchtowers, granaries, and even a civilian residential area.

Near the Serbian border, Croatia's easternmost city is known for its grit. During the War of Independence in the 1990s, it was almost completely destroyed after an 87-day siege. Vukovar rebuilt, and the Old Town is once again a magnet for guests from around the world. Highlights include the town's famous water tower, whose battered structure is a symbol of the proud Croatian spirit; the poignant National Memorial Cemetery of the Victims of Homeland War, the nation's largest mass grave; and elegant Eltz Manor, the 18th-century Baroque home of the Vukovar City Museum.

Kalocsa is one spicy city! The self-proclaimed "Paprika Capital of the World" is one of Hungary’s oldest cities, filled with historic buildings and quaint shops (selling paprika—what else?). Highlights include the 200-year-old Folk Art House, where local female artisans still paint furnishings, eggs, and other items in the traditional Hungarian way; the Paprika House, a museum dedicated to the legendary Hungarian spice; and the Archbishop's Palace with its 150-thousand-volume library of ancient books and manuscripts.