Narrated (Abdullah) bin 'Umar:

The Prophet arrived (at Mecca) in the year of the Conquest (of Mecca) while Usama was riding behind him on (his she-camel)'. Al-Qaswa.' Bilal and 'Uthman bin Talha were accompanying him. When he made his she-camel kneel down near the Ka'ba, he said to 'Uthman, "Get us the key (of the Ka'ba). He brought the key to him and opened the gate (of the Ka'ba), for him. The Prophet, Usama, Bilal and 'Uthman (bin Talha) entered the Ka'ba and then closed the gate behind them (from inside). The Prophet stayed there for a long period and then came out. The people rushed to get in, but I went in before them and found Bilal standing behind the gate, and I said to him, "Where did the Prophet pray?" He said, "He prayed between those two front pillars." The Ka'ba was built on six pillars, arranged in two rows, and he prayed between the two pillars of the front row leaving the gate of the Ka'ba at his back and facing (in prayer) the wall which faces one when one enters the Ka'ba. Between him and that wall (was the distance of about three cubits). But I forgot to ask Bilal about the number of Rakat the Prophet had prayed. There was a red piece of marble at the place where he (i.e. the Prophet) had offered the prayer.

حَدَّثَنِي مُحَمَّدٌ، حَدَّثَنَا سُرَيْجُ بْنُ النُّعْمَانِ، حَدَّثَنَا فُلَيْحٌ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ أَقْبَلَ النَّبِيُّ ﷺ عَامَ الْفَتْحِ وَهْوَ مُرْدِفٌ أُسَامَةَ عَلَى الْقَصْوَاءِ. وَمَعَهُ بِلاَلٌ وَعُثْمَانُ بْنُ طَلْحَةَ حَتَّى أَنَاخَ عِنْدَ الْبَيْتِ، ثُمَّ قَالَ لِعُثْمَانَ " ائْتِنَا بِالْمِفْتَاحِ "، فَجَاءَهُ بِالْمِفْتَاحِ فَفَتَحَ لَهُ الْبَابَ، فَدَخَلَ النَّبِيُّ ﷺ وَأُسَامَةُ وَبِلاَلٌ وَعُثْمَانُ، ثُمَّ أَغْلَقُوا عَلَيْهِمِ الْبَابَ، فَمَكَثَ نَهَارًا طَوِيلاً ثُمَّ خَرَجَ، وَابْتَدَرَ النَّاسُ الدُّخُولَ، فَسَبَقْتُهُمْ فَوَجَدْتُ بِلاَلاً قَائِمًا مِنْ وَرَاءِ الْبَابِ فَقُلْتُ لَهُ أَيْنَ صَلَّى رَسُولُ اللَّهِ ﷺ فَقَالَ صَلَّى بَيْنَ ذَيْنِكَ الْعَمُودَيْنِ الْمُقَدَّمَيْنِ. وَكَانَ الْبَيْتُ عَلَى سِتَّةِ أَعْمِدَةٍ سَطْرَيْنِ، صَلَّى بَيْنَ الْعَمُودَيْنِ مِنَ السَّطْرِ الْمُقَدَّمِ، وَجَعَلَ باب الْبَيْتِ خَلْفَ ظَهْرِهِ، وَاسْتَقْبَلَ بِوَجْهِهِ الَّذِي يَسْتَقْبِلُكَ حِينَ تَلِجُ الْبَيْتَ بَيْنَهُ وَبَيْنَ الْجِدَارِ، قَالَ وَنَسِيتُ أَنْ أَسْأَلَهُ كَمْ صَلَّى وَعِنْدَ الْمَكَانِ الَّذِي صَلَّى فِيهِ مَرْمَرَةٌ حَمْرَاءُ.