Sunan Abi Dawud Book 42, Hadith 43
The Romans will enter the Levant and stay there for forty days, and no place will be saved from them but Damascus and 'Uman.
Messenger of Allah (ﷺ)! I saw (in a dream) that a bucket was hung from the sky. Abu Bakr came, caught hold of both ends of its wooden handle, and drank a little of it. Next came ‘Umar who caught hold of both ends of its wooden handle and drank of it to his fill. Next came ‘Uthman who caught hold of both ends of its handle and drank of it to his fill. Next came ‘All. He caught hold of both ends of its handle, but it became upset and some (water) from it was sprinkled on him.
A king of the foreigners will come and prevail over all the cities except Damascus.