كتاب الجنة وصفة نعيمها وأهلها
53  
The Book of Paradise, its Description, its Bounties and its Inhabitants
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Chapter: In Paradise There Is A Tree In Whose Shade A Rider Could Travel For One Hundred Years And Still Not Cross It
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باب إِنَّ فِي الْجَنَّةِ شَجَرَةً يَسِيرُ الرَّاكِبُ فِي ظِلِّهَا مِائَةَ عَامٍ لاَ يَقْطَعُهَا ‏‏
Sahih Muslim 2826 b

This hadith has been narrated on the authority of Abu Huraira through another chain of transmitters with the addition of these words:

" He will not be able to cover this distance."
حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا الْمُغِيرَةُ، - يَعْنِي ابْنَ عَبْدِ الرَّحْمَنِ الْحِزَامِيَّ - عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم بِمِثْلِهِ وَزَادَ ‏ "‏ لاَ يَقْطَعُهَا ‏"‏ ‏.‏
Reference : Sahih Muslim 2826b
In-book reference : Book 53, Hadith 8
USC-MSA web (English) reference : Book 40, Hadith 6785
  (deprecated numbering scheme)