Sahih Muslim
The Book Pertaining to the Excellent Qualities of the Holy Prophet (may Peace be upon them) and His Companions (Kitab Al-Fadail)
Book Number: 030 / Hadith Number: 5711
Jabir b. Samura reported Allah's Messenger (may peace be upon him) as saying: Behold, I shall be present ahead of you on the Cistern, and the distance between its different sides would be like that between Sana' and Aila, and its jugs would be like stars in the sky.