The Messenger of Allah ﷺ said, "In Paradise there is a tree under whose shade a rider can travel for a hundred years without crossing it. It is the tree of eternity."
حدثنا عبد الرحمن قال حدثنا شعبة عن أبي الضحاك قال سمعت
قال رسول الله ﷺ إن في الجنة شجرة يسير الراكب في ظلها مائة عام لا يقطعها شجرة الخلد
Its isnad is sahih. Abu Dahhak's name is his kunya, he is accepted (maqbul), and the hadith has already appeared at 9793.