Budapest is the capital city of Hungary. As the largest city of Hungary, it serves as the country's principal political, cultural, commercial, industrial, and transportation center and is considered an important hub in Central Europe. In 2008, Budapest had 1,702,297 inhabitants with an official agglomeration of 2,451,418, down from a mid-1980s peak of 2.1 million. The city covers an area of 525 square kilometres within the city limits. Budapest became a single city occupying both banks of the river Danube with the unification on 17 November 1873, of right-bank Buda and Óbuda together with Pest on the left bank. Aquincum, originally a Celtic settlement, was the direct ancestor of Budapest, becoming ...

  ... the Roman capital of Lower Pannonia. Magyars arrived in the territory in the 9th century. Their first settlement was pillaged by the Mongols in 1241-42. The re-established town became one of the centers of Renaissance humanist culture in the 15th century. Following nearly 150 years of Ottoman rule, development of the region entered a new age of prosperity in the 18th and 19th centuries, and Budapest became a global city after the 1873 unification. It also became the second capital of Austria-Hungary, a great power that dissolved in 1918. Budapest was the focal point of the Hungarian Revolution of 1848, the Hungarian Soviet Republic of 1919, Operation Panzerfaust in 1944, the Battle of Budapest of 1945, and the Revolution of 1956. Widely regarded as one of the most beautiful cities in Europe, its World Heritage Sites include the banks of the Danube, the Buda Castle Quarter, Andrássy Avenue, and the Millennium Underground Railway, the first on the European continent. Budapest attracts over 20 million visitors a year. The city ranks 52nd on MasterCard's 'World's Top 75 Financial Centers' list and 74th on Mercer Consulting's 'World's Top 100 Most Livable Cities' list. The headquarters of the European Institute of Innovation and Technology will be in Budapest