Sunnan Abu Dawud Collection: ::Book Number 10:: Hadith # 1738
Narrated Al-Harith ibn Amr as-Sahmi: I came to the Apostle of Allah (peace_be_upon_him) when he was at Mina, or at Arafat. He was surrounded by the people. When the bedouins came and saw his face, they would say: This is a blessed face. He said: He (the Prophet) appointed Dhat Irq as the place of putting on ihram for the people of Iraq.