Muhammad’s Hijrah journey from Mecca to Medina founds the Islamic calendar
The Hijrah migration began in the summer of 622 C.E., when Muhammad and Abu Bakr slipped out of Mecca by night, hid three days in a cave, then rode 260 miles north to Medina. There, a compact among Muslim, Jewish, and Arab tribes took shape — a founding moment still anchoring the calendar of roughly 1.9 billion Muslims today.