Budapest later, with the help of the Russian Empire. 1867 was the year of Reconciliation that brought about the birth of Austria-Hungary. This made Budapest the twin capital of a dual monarchy. It was this compromise which opened the second great phase of development in the history of Budapest, lasting until World War I. In 1849 the Chain Bridge linking Buda with Pest was opened as the first permanent bridge across the Danube and in 1873 Buda and Pest were officially merged with the third part, Óbuda (Old Buda), thus creating the new metropolis of Budapest. The dynamic Pest grew into
Budapest are currently 837 different monuments, which represent the most of the European artistic style. The classical and unique Hungarian Art Nouveau buildings are prominent. A lot of libraries have unique collections in Budapest, such as the National Széchenyi Library, which keeps historical relics from the age before the printing of books. The Metropolitan Szabó Ervin Library plays an important role in the general education of the capital's population. Other libraries: The Library of the Hungarian Academy of Sciences, Eötvös University Library, the Parliamentary Library, Library of the Hungarian Central Statistical Office and the National Library of Foreign Literature. In Budapest