The picture above shows the Hajar al-Aswad (The Black Stone), which is set in the eastern corner of the Ka’bah. Tawaf begins and ends facing this sacred stone. Throughout the ages, countless people including many of the Prophets (upon them be peace), the Prophet Muhammad (ﷺ) himself, the Sahabah (رضي الله عنهم), pious personalities and millions of Muslims who have performed Hajj and Umrah have placed their blessed lips on it.
Featured image: https://qamarislamkhan.com/hajr-e-aswad-the-holy-black-stone/