The Biblioteca Archeologica e Numismatica, founded in 1808 inherited the rare archival and book collections from the Brera Numismatic Collection (1808-1917) and from the National Museum of Archaeology (1863-1903). Following the agreement between the Ministry of Education and the City of Milan on 18th May 1916 stipulating the housing of the state numismatic and archaeological collections at the Sforza Castle, the Library was transferred to the castle, and housed in two rooms adjacent to the Treasury Room and the Rocchetta Courtyard.  Following the Second World War it was again moved to the Umberto I tower and in the past years has been providing a regular service, supported also by external holdings.