Hajj is the annual Islamic pilgrimage closely linked to Eid al-Adha.
Hajj takes place in and around Mecca, in present-day Saudi Arabia, during Dhu al-Hijjah. Its main rites traditionally occur from the 8th through the 12th or 13th day of the month. Eid al-Adha begins on the 10th day, following the Day of Arafah, so the pilgrimage and festival overlap in both timing and religious themes.
Hajj is one of the Five Pillars of Islam. Muslims who are physically and financially able to make the journey are generally required to perform it once in their lifetime. Pilgrims perform rites including circling the Kaaba, traveling between Safa and Marwah, standing at Arafat, spending time at Muzdalifah, and symbolically stoning pillars at Mina.
Umrah is sometimes called the lesser pilgrimage and can be performed at other times of year; it does not replace Hajj for someone who is obligated to perform Hajj. Arba'in is a different pilgrimage associated especially with Shi'a Muslim remembrance of Imam Husayn.