The Messenger of Allah ﷺ used to spend the last ten days of Ramadan in I’tikaf. Nafi' said: " Abdullah bin 'Umar showed me the place where the Messenger of Allah ﷺ used to observe I'tikaf."  

أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ يَعْتَكِفُ الْعَشْرَ الأَوَاخِرَ مِنْ رَمَضَانَ قَالَ نَافِعٌ وَقَدْ أَرَانِي عَبْدُ اللَّهِ بْنُ عُمَرَ الْمَكَانَ الَّذِي كَانَ يَعْتَكِفُ فِيهِ رَسُولُ اللَّهِ ﷺ  

When the Prophet ﷺ observed I’tikaf, his bedding would be spread for him, or his bed would be placed there for him, behind the Pillar of Repentance.  

عَنِ النَّبِيِّ ﷺ أَنَّهُ كَانَ إِذَا اعْتَكَفَ طُرِحَ لَهُ فِرَاشُهُ أَوْ يُوضَعُ لَهُ سَرِيرُهُ وَرَاءَ أُصْطُوَانَةِ التَّوْبَةِ