The Collections of the Library and the Archive were created in the second half of the 19th century, when Mr Francisco de Zabálburu collected high-quality antique books assessed by a team of experts, such as José Sancho Rayón, librarian of the Spanish Department of Development at that time, Alphonse Guépin, the abbot of Silos and member of the Spanish Royal Academy of History, and his successor, the historian Luciano Serrano.
He acquired the whole collection by purchasing from individuals, antiquarian booksellers or at auctions in Spain and particularly France. They classified each of the books with strict scientific rigour in descriptive sheets, creating the files that are still preserved.
They also installed and distributed the 10,000 books in the Room and the cabinets prepared for such purpose. The Archive is half of that which was created by the House of Altamira through history and by joining several Spanish noble houses.