The Islamic calendar is the only widely used purely lunar calendar, its year varying from 354 to 355 days. Hence the seasons and months have no connection, and there are about 33 years to every 32 Gregorian years. The months are Muharram (30), Safar (29), 1st Rabia (30), 2d Rabia (29), 1st Jumada (30), 2d Jumada (29), Rajab (30), Shaban (29), Ramadan (the fast, 30), Shawwal (29), Dhu-l-Kada (30), and Dhu-l-Hijja (month of the pilgrimage, 29 or 30). The first day of the Islamic calendar, Muharram 1, A.H. 1, was July 16, 622, in the Western calendar (A.H. [Anno Hegirae = in the year of the Hegira] is used to indicate the Islamic year). Muharram 1, A.H. 1420 was Apr. 17, 1999.
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