"Fasti" is a poetic work of the Roman poet Ovid, consisting of six books. In this work, the author talks about Roman holidays, rituals and mythology related to the Roman calendar. Each month of the year is presented separately with all the holidays and rituals associated with it. This work is an important source for the study of Roman religion and culture during the time of Caesar and Octavian. Ovid combined mythological stories with descriptions of real rituals in "Fasti", which makes the book a fascinating read for those interested in the ancient world.