In Islam, hajj is the pillar that requires Muslims who are physically and financially able to do so to make a pilgrimage to Mecca. It is required once in a lifetime under the usual conditions of capability.
Hajj takes place during specific days of Dhu al-Hijjah, the final month of the Islamic calendar. Its rites include entering ihram, circumambulating the Kaaba, traveling between Safa and Marwa, standing at Arafat, and spending time at Mina.
Hajj is distinct from umrah, the lesser pilgrimage, which can be performed at other times of year. The obligation also includes the condition of ability, so Islamic law does not treat the pilgrimage as universally required for people unable to undertake it safely or affordably.