The plain area adjoining the hill is called the ground of Arafat. The term Mount `Arafat is usually applied to this entire area. It is an important place because during Hajj, pilgrims have to be present there in “Ahram” between the afternoon of the 9th day of Dhul Hijjah & before the (Fajir) time starts of the 10th day of Dhul Hijjah. Failure to be present in the plain of Arafat on the required time invalidates the pilgrimage. For more information about Hajj-Umrah in our link.