1. The world-famous music capital is Vienna.

2. Vienna, located on the Danube River, is the capital and largest city of Austria. It is one of the nine federal states in the country and a major cultural center in Europe. It is known as the "Music Capital of the World" ".

3. Vienna is the most populous city in Austria. In the 2017 census, Vienna had a population of more than 1.87 million. Vienna is also the second most populous German-speaking city in the world, after Berlin.

4. Vienna is one of the four official residences of the United Nations. It is also the headquarters of the Organization of the Petroleum Exporting Countries, the Organization for Security and Cooperation in Europe, the International Atomic Energy Agency, and the seat of other international institutions. Vienna has been rated as one of the most livable cities in the world by the United Nations Human Settlements Program for many years in a row.