The Cathedral and its Cloister, together with the nearby Palazzo Ducale and the imposing building of the Palazzetto Criminale, now the seat of the State Archives, constituted the political, religious and legislative center of the ancient aristocratic Republic. In 1923 the Canons of the Cathedral sold the Cloister, their residential headquarters, to the Municipality of Genoa: while remaining united by a suspended pier that still connects them, it was only thanks to the agreement to host the Diocesan Museum in the Cloister that the complex was able to find the its religious and cultural unity. Inside the Cathedral is the Treasure Museum, designed by Franco Albini and consid-ered one of the highest achievements of modern museography.