In the actual year when the migration took place, there was already a functioning Lunar calendar with named months. However, this calendar did not number the years, so for example, the year Prophet Muhammad and Ammar ibn Yasir were born was called "The Year of the Elephant". That year was named "The permission to travel". Seventeen years later, that year was chosen as the year to start counting from: first year of Hijra, 1 Anno Hegirae or 1 AH. The first day of 1 AH corresponds to July 16, 622 CE in the Julian Calendar,[1] denoted as "1 Muharram 1 AH". From this we can mark the beginning of hijrah and also mark seventeen years later as the year the hijri Callender was made incumbent