The Prophet ﷺ said, "O Allah, place in Medina twice the blessing You placed in Mecca."
عن النبي ﷺ قال: اللهم اجعل بالمدينة ضعفي ما جعلت بمكة من البركة.
Narrated by Bukhari in the Virtues of Madinah (1885), and Muslim in the Book of Hajj (1369-466), both through routes going back to Wahb bin Jareer, who said, my father narrated to us, I heard Yunus, from Ibn Shihab, from Anas, who related it.Regarding the word "double" in the supplication, the reason for this prayer for Madinah was that Madinah was a small city, and its dwellings and agricultural lands were limited, while migration to it was continuous. The Prophet ﷺ feared the shortage of housing and means of livelihood, so he made this supplication, and Allah answered his prayer. Within ten years, the population of Madinah grew tenfold, and yet it still had room for everyone who migrated to it.