Answer: Hijra 622nd year.
Step-by-step explanation:
It represents the relocation of the Prophet Muhammad from Mecca to Medina. The reasons they brought were the pressure on members of Islam by other nations. Muslims were, therefore forced to abandon Mecca because of their religious beliefs.
There is evidence that Muslims have voluntarily left Mecca, but that information is misleading. Some sources say that Muslims were inhabited during that period, which was more than sufficient reason for Hijra.