The river that flows through Budapest is the Danube. This iconic river is the second-longest in Europe and plays a significant role in the history, culture, and economy of the region. Flowing through several countries, the Danube is lined with historic cities, castles, and scenic landscapes. In Budapest, the river divides the city into Buda and Pest, offering picturesque views and recreational opportunities. The Danube also serves as a major transportation route and is vital for tourism and commerce.