Sahih Muslim Book 7, Hadith Number 2661.

Chapter : The place where the pilgrims enter upon the state of Ihram.

Ibn ‘Umar (Allah be pleased with them) reported that the Messenger of Allah (may peace be upon him) said: The people of Medina should enter upon the state of Ihram at Dhu’l-Hulaifa, and people of Syria at Juhfa, and people of Najd at Qarn (al-Manazil), and ‘Abdullah (further) said: It has reached me that the Messenger of Allah (may peace be upon him) also said: The people of Yemen should enter upon the state of Ihram at Yalamlam.