Parmigiani FleurierTonda PF Hijri Perpetual CalendarRef: PFH983-1020001-100182

The TONDA PF Hijri Perpetual Calendar is a horological expression of the Tabular Islamic calendar developed by Muslim scholars and astronomers in the 8th century. This system made it possible for historians to convert Islamic dates to Gregorian dates, which in turn has made the Hijri Perpetual Calendar possible. The first year of the Hijri calendar corresponds to the year 622 CE and is marked by the Prophet Muhammad’s Hijrah (Arabic for “migration”) from Mecca to Medina in what is today Saudi Arabia. The lunar Hijri calendar is based on the cycles of the moon, in comparison to the solar Gregorian calendar and lunisolar Chinese Xiali calendar. This makes for a 30-year cycle with each year consisting of 12 months that are 29 or 30 days long. In each 30-year cycle there are 19 common years of 354 days and 11 abundant years of 355 days.