Dubrovnik Libraries is a public cultural institution founded by the City of Dubrovnik. It has a dual function and comprises of two institutions: Public library and Research library. The Research library takes pride in its many heritage collections (manuscripts, correspondence, librettos, books, incunabula). The basis for the Library were gifts of the citizens of Dubrovnik and of (aristocratic) families, and also the collections belonging to the former library of the Jesuit Collegium Rhagusinum. One of the most significant collections is Ragusina, which consists of books, periodicals, manuscripts, correspondence, ephemera, audiovisual and electronic materials which either originate from Dubrovnik or are thematically linked to Dubrovnik and the area of the old Dubrovnik Republic. Another priceless collection is the Collection of incunabula which today holds 81 item. Not less significant is the Old and rare book collection. It was formed by combining the collection Collegium Rhagusinum with private collections that came from several Ragusan families. The books date from the 16th to mid-19th century. The oldest item in the Library's holdings (from 10th/11th century) comes from the Collection of manuscripts.