From Sahih Bukhari (Hadith 1522):
Narrated Zaid bin Jubair:I went to visit `Abdullah bin `Umar at his house which contained many tents made of cotton cloth and these were encircled with Suradik (part of the tent). I asked him from where, should one assume Ihram for Umra. He said, "Allah's Messenger (ﷺ) had fixed as Miqat (singular of Mawaqit) Qarn for the people of Najd, Dhul-Hulaifa for the people of Medina, and Al-Juhfa for the people of Sham
Reference: Bukhari 1522