The Canons' Cloister of San Lorenzo was built between the Cathedral, the Criminal Palace and Palazzo Ducale between 1176 and 1184 on a pre-existing oldest bishop's palace. The construction of the twelfth century replaced a first cloister erected near the site of St. John and it's characterized by two levels of arches on twin columns. The current structure was created by remodeling since the thirteenth century, with the decoration of the wooden floors, while, at the fourteenth century are ascribed the paintings wall of the rooms on the first floor ("Hall of Marmoreal Mirrorings", "Cycle of the Months"). In the middle of `600 the structure is elevated two-story Romanesque arcades and replaced, for both sides, with large arches supported by pillars; in '700 is done with the frescoes of the upper gallery celebrating the "Splendours of the Chapter". Abandoned by the canons from the second half of the 800 until the Second World War, is used as a dwelling. In 1958, the precarious conditions forced the demolition of two raised floors and, in 1985, began the recovery of the entire complex with a complete restoration of the different components and building phases for the use and destination in the Diocesan Museum. Historical memory of the most significant stages of the Church of Genoa, today is a full part of the monumental center and museum that also includes the Cathedral of San Lorenzo and the Treasure Museum.