Zoroastrianism has numerous festivals and holy days, all of which are bound to the Zoroastrian calendar. The Shahenshahi and Kadmi variants of the calendar do not intercalate leap years and hence the day of the Gregorian calendar year on which these days are celebrated shifts ahead with time. The third variant of the Zoroastrian calendar, known as either Fasli (in India) or Bastani (in Iran), intercalates according to Gregorian calendar rules and thus remains synchronous with the seasons. For details on the differences, see Zoroastrian calendar. Six irregularly-spaced seasonal festivals, called gahanbars (meaning "proper season"), are celebrated during the religious year. The six festivals are additionally associated with the six "primordial creations" of Ahura Mazda, otherwise known as the Amesha Spentas, and through them with aspects of creation (the sky, the waters, the earth, plant life, animal life, humankind). Due to the peculiarities of the Shahenshahi and Kadmi variants of the Zoroastrian calendar, which do not intercalate and are therefore no longer synchronized with the seasons, the seasonal festivals are actually celebrated many months in advance. The six festivals are: Maidyozarem Gahanbar (literally: 'midgreening'), originally celebrated as a mid-spring festival. Maidyoshahem Gahanbar ('midsummer'), originally celebrated on the summer solstice. Paitishahem Gahanbar ('bringing in the corn'), originally celebrated as a harvest festival. Ayathrem Gahanbar ('bringing home (the herds)'), originally celebrated at the end of autumn. Maidyarem Gahanbar ('mid-year'), originally celebrated on the winter solstice. Hamaspathmaidyem Gahanbar (for which there is no generally accepted literal meaning), celebrating mankind.This gagambar is not a seasonal festival in the technical sense, but rather commemorates the souls of the dead at the end of the religious year. It is better known as frawardigan. In the present day, each of these festivals is celebrated over five days, except Hamaspathmaidyem Gahambar, which is held over ten days (two five-day periods, see "other holy days" below).