Sahih al-Bukhari 6552
صحيح البخاري#6552SahihNarrated Sahl bin Sa'd: Allah's Messenger (ﷺ) said, "In Paradise there is a tree so big that in its shade a 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: 81:141