Vienna is the national capital, largest city, and one of nine states of Austria. Vienna is Austria's most populous city whose population is about 1.9 million (2.6 million within the metropolitan area and around one third of the country's population), and its cultural, economic, and political centre. It is the 7th largest city by population within city limits in the European Union.
In 20th century, it was the largest German-speaking city in the world, and before the splitting of the Austro-Hungarian Empire in World War I, the city had 2 million inhabitants. Now, it is the second-largest German-speaking city after Berlin. Vienna is host to many major international organizations, including the United Nations, OPEC, and the OSCE. The city is located in the eastern part of Austria and is close to the borders of Czechia, Slovakia, and Hungary. The city centre was designated a UNESCO World Heritage Site in 2001 and in 2017 it was moved to the list of World Heritage in Danger.