"Mist, not smoke, rose from the water at the confluence of the Danube and the Sava rivers. This is the point where the biggest city in the Balkans began. Belgrade's origins lie in a Celtic settlement on a bluff with superb views across the plains. Today, the horizon is scarred with chimneys and tower blocks, but the drama of the location remains. Beneath the ridge, skeletal trees accompany the Sava to the point where it merges into, and amplifies, the artery of eastern Europe. As the Danube continues its stately progress towards the Black Sea, you can understand why the Romans, Slavs, Turks and Austrians took turns to command these heights. Nowadays, the gently decaying stratum of history known as Belgrade fortress, draped upon the high ground, is the preserve of tourists."