Hajj - The pilgrimage to the Kab'ah in Makkah that is required of every able Muslim at least once in a lifetime. Hajj is performed during Dhul-Hijjah from the 8th to the 12th or 13th and a piligrim needs to perform certain prescribed rites of worship during this period.
A compulsory duty on all adult Muslims of sound mind and body once n a lifetime if they are economically and physically able.