Abu Hurairah narrated that the Messenger of Allah (s.a.w) said:
"In Paradise, there are a hundred levels, between every two levels is (the distance of) a hundred years." (RU)
English reference (RU): Vol. 4, Book 12, Hadith 2529 (RU)
Arabic reference (RU): Book 38, Hadith 2721 (RU)