The Cathedral of Cefalù, according to legend, arose as a result of the vow made by Roger II to the Holy Saviour, to escape a storm and landed on the beaches of the town. The real motivation seems more a political-military, given its character as a fortress. The events were building complex, with significant variations from the original draft, and the building was never completed finally. An ambulatory proceeds into the wall and the same cover, consisting of three roofs, dating and other construction techniques, evidence of changes in the project.