what are other places in this city that are considered significant in islam?
The Hira cave, Great Mosque of Makkah
Mecca
The Hira cave atop the "Jabal al-Nur" ("Mountain of Light") is just outside the city and is where Muslims believe the Qur'an was first revealed to Muhammad. Visiting Makkah for the Hajj is an obligation upon all able Muslims. The Great Mosque of Makkah, known as the "Masjid al-Haram", is home to the Ka'bah, believed by Muslims to have been built by Abraham and Ishmael, is one of Islam's holiest sites and the direction of prayer for all Muslims ("qibla"), cementing Makkah's significance in Islam.
when did two million pilgrims make the hajj UNANSWERABLE is it a religious pilgrimage? Yes, it  is an annual Islamic pilgrimage,  a mandatory religious duty for Muslims that must be carried out at least once in their lifetime where does it take place? Mecca, Saudi Arabia, the holiest city for Muslims. the city mentioned what are the major events in its early history? The Roman Empire took control of part of the Hejaz in 106 CE, ruling cities such as Hegra
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Mecca [SEP] Introduction
Visiting Makkah for the Hajj is an obligation upon all able Muslims. The Great Mosque of Makkah, known as the "Masjid al-Haram", is home to the Ka'bah, believed by Muslims to have been built by Abraham and Ishmael, is one of Islam's holiest sites and the direction of prayer for all Muslims ("qibla"), cementing Makkah's significance in Islam. Muslim rulers from in and around the region long tried to take the city and keep it in their control, and thus, much like most of the Hejaz region, the city has seen several regime changes, which owes to its rich history.