question #2 Sahih Muslim 1182a, Book 15, Hadith 15 : Why is it important for pilgrims to enter the state of Ihram at specific locations?

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 (ﷺ) also caid: The people of Yemen should enter upon the state of Ihram at Yalamlam.