Musnad Ahmad 27:1093

Muhammad ibn Abd al-Rahman narrated to us, Ayyub narrated to us, from Nafi, from Ibn Umar, that he heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "The *miqat* (appointed place for entering ihram) for the people of Medina is Dhu al-Hulayfah, the *miqat* for the people of Syria is al-Juhfah, and the *miqat* for the people of Najd is Qarn." The people then said: "The *miqat* for the people of Yemen is Yalamlam."