Budapest is the capital city of Hungary and the country's principal political, cultural, commercial, industrial and transportation center. Budapest has approximately 1.7 million inhabitants, down from a mid-1980s peak of 2.1 million. Budapest became a single city occupying both banks of the river Danube with the amalgamation on 17 November 1873 of right-bank Buda (Ofen in German) and Óbuda (Old Buda or Alt-Ofen) together with Pest on the left (east) bank. It is the seventh largest city in the European Union. Budapest's districts are numbered clockwise, in widening circles, and are organized similarly to the arrondissements in Metropolitan Paris.