The Berlin State Library, established in 1661 as Churfürstliche Bibliothek zu Cölln an der Spree, features a long and dynamic history. During the first years of its existence the institution was housed in a wing of Berliner Schloss. In 1701, it was renamed Königliche Bibliothek zu Berlin, or Berlin Royal Library and began to expand gradually, supported by the monarchy and declared a Prussian Cultural Heritage. This remarkable development was interrupted by the Nazi regime and the World War II. In 1914, the library was moved to its current venue and four years later it was renamed Preußische Staatsbibliothek, or Prussian State Library. In 1933, a horrific book burning organised by the Nazi minister of propaganda Joseph Goebbels took place on Bebelplatz, where more than 20,000 books taken from the library were destroyed. During the war all the books and other materials, amounting to 3 million at that time, were hidden in 30 monasteries, castles and abandoned mines. After 1945, they were divided between the library sites in East and West Berlin. Following the reunification of Germany. In 1992, the Berlin State Library became a united institution and nowadays it provides services to the public in both its venues. Today, the library has devoted itself completely to the aim of protecting the immense cultural treasure, stored in it, and to active research. The institution is supported by numerous organisations, such as Friends of the Berlin State Library and the Mendelsson Society. Visitors have the choice between more than 10 departments, including many international materials, plus on-line services and book stores.