Which European capital is split by the Danube into Buda and Pest?

The Danube cuts a broad north-to-south channel through the Hungarian capital, and the two banks could hardly be more different. On the western side, Buda climbs steep hills crowned by the royal castle and the medieval quarter; on the eastern side, Pest spreads flat across the plain and holds the wide boulevards, the grand parliament building on the embankment and most of the commercial life. They were separate towns for centuries, each with its own charter and character, and only merged in 1873 along with Óbuda, the older settlement upstream. The permanent bridges that made unification practical came first in the nineteenth century, before which crossings depended on boats or a seasonal pontoon. The city's other signature feature also comes from its geology: fault lines beneath Buda feed hot mineral springs, which the Romans and later the Ottomans both built bathhouses over, and which still supply the thermal baths today.

The Danube passes more national capitals than any other river, flowing through four of them on its way to the Black Sea.