Sahih al-Bukhari 6553
صحيح البخاري#6553SahihNarrated Abu Sa'id: The Prophet (ﷺ) said: There is a tree in Paradise (so huge) that a fast (or a trained) rider may travel: for one hundred years without being able to cross it
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 81:142