Sahih Muslim Book 7, Hadith Number 3162.

Chapter : Eminence of Medina, Allah’s Apostle (may peace be upon him) showered blessings upon it. Its sacredness and unlawfulness of hunting and lopping of trees and demarcation its precincts.

Anas b. Malik (Allah he pleased with him) reported that Allah’s Messenger (may peace be upon him) said: O Allah, increase in Medina twice the blessings (Thou showered) on Mecca.