Messenger of Allah ﷺ performed the Tawaf (around the Kaʿba while riding his camel, and every time he reached the corner (of the Black Stone) he pointed at it with his hand and said, "Allahu Akbar." (Zainab said: The Prophet ﷺ said, "An opening has been made in the wall of Gog and Magog like this and this," forming the number 90 (with his thumb and index finger). (Using translation from Bukhārī 5293)
طَافَ رَسُولُ اللهِ ﷺ عَلَى بَعِيرِهِ فَكُلَّمَا أَتَى عَلَى الرُّكْنِ أَشَارَ إِلَيْهِ وَكَبَّرَ