Wheel of the Year the last month of the old year and the first month of the new year and is followed by eleven days of extended celebration. In Roman traditions additional festivities take place during the six days leading up to Midwinter. As the first cross-quarter day following Midwinter this day falls on the first of February and traditionally marks the first stirrings of spring. It aligns with the contemporary observance of Groundhog Day. It is time for purification and spring cleaning in anticipation of the year's new life. In Rome, it was historically a shepherd's holiday, while the Celts associated it with
Leap year lunar months containing 29 or 30 days, generally in alternating order. However, the tabular Islamic calendar used by Islamic astronomers during the Middle Ages and still used by some Muslims does have a regular leap day added to the last month of the lunar year in 11 years of a 30-year cycle. This additional day is found at the end of the last month, Dhu 'l-Hijja, which is also the month of the Hajj. The Hijri-Shamsi calendar, also adopted by the Ahmadiyya Muslim Community, is based on solar calculations and is similar to the Gregorian calendar in its structure with