Belgrade Loop on the Lower Danube with Iron Gates

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.

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.

One of the Danube’s most breathtaking natural wonders is the dramatic “Iron Gates”. Here, rugged canyon walls soar up to 984 feet (300 meters) above the river, creating a scene like something from a movie. Declared a UNESCO global geopark in 2020, this incredible geological feature separates the Carpathian and Balkan Mountains, forms the border between Serbia and Romania, and is home to Iron Gates Natural Park and Đerdap National Park.

During its long and tumultuous history, Vidin has seen some things. It’s a place with ancient Roman roots. It was subjugated for half a millennium by the Ottoman Turks, and it suffered a devastating flood in 1942. Today Vidin provides a major border crossing to neighboring Romania. The Old Town is an engaging potpourri of architectural diversity that includes austere structures from the Socialist era. Highlights include many old Orthodox churches, a synagogue, mosque, indominatable Baba Vida fortress, and a growing reputation for its wine production.

Giurgiu sits among the mud flats and marshes of the Danube's left bank. Three small islands face the city, and a larger one shelters its port. This one-time exporter of timber, grain, salt, and petroleum was served by a railway to Bucharest that was built in 1869, the first line opened in Romania. This also placed Giurgiu on the map among wealthy globetrotters as it became a stop for the legendary Orient Express. By 1954, Giurgiu had another feather in its cap, when the steel-truss Friendship Bridge opened over the Danube, connecting Romania to neighboring Bulgaria.

The city of Rousse on the right bank of the Danube grew from a Neolithic settlement into one of modern Bulgaria's key cultural and economic centers. Its beautiful Neo-Baroque and Neo-Rococo architecture, wide boulevards, and green squares earned it the nickname "Little Vienna". Highlights include its beautiful Opera House, Palace of Justice, Freedom Square, and Freedom Bridge, which crosses the Danube to Giurgiu, Romania, and elevated Rousse to Bulgaria's most significant river port.

Svistov, the Danube’s southernmost point, has endured a turbulent past—battles between Romans and barbarians, devastation during the Russo-Turkish War, a Russian sacking in 1878, and near destruction from a 1977 earthquake. Despite these hardships, it recovered as an agricultural, fishing, cultural, and university center. The Old Town retains its character with winding alleys, well-preserved historic buildings, and a scenic riverside promenade, all watched over by the Cathedral of the Holy Trinity, which has stood proudly on the highest hill since 1867.

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.