Mecca is the spiritual center of Islam, home to the Kaaba within the Masjid al-Haram, toward which Muslims worldwide orient their five daily prayers and around which pilgrims circumambulate during the annual Hajj. The Prophet Muhammad was born here around 570 CE, received the first Quranic revelations in the cave of Hira on Jabal al-Nour, and returned with his community in 630 CE to rededicate the sanctuary to monotheistic worship. The Masjid al-Haram, expanded continuously under the Abbasids, Ottomans, and the modern Saudi state, now accommodates over a million worshippers, while the nearby Plain of Arafat and the towns of Mina and Muzdalifah form the ritual geography of the Hajj. Mecca's significance is not historical alone: every year roughly two to three million pilgrims perform Hajj, tens of millions perform Umrah, and the city sustains a year-round culture of recitation, ritual hospitality, and scholarship around the Haram.