الحجر الأسود
The Hajar al-Aswad (Hajar Aswad) is a sacred stone set into the eastern corner of the Kabah in Mekkah. Muslims begin and end each circuit of tawaf at this point. Nabi Muhammad (PBUH) placed it in its current position during the Kabah's reconstruction.
The Hajar Aswad is believed by Muslims to date back to the time of Prophet Adam (AS) and was originally white, turning black from absorbing the sins of humanity. When the Quraysh rebuilt the Kabah, a dispute arose over who should place the stone. Prophet Muhammad (PBUH) resolved it by having representatives of each clan hold a cloth carrying the stone, then placing it himself. The stone has been broken into fragments over the centuries and is now held together by a silver frame.
The Hajar Aswad marks the starting and ending point of tawaf. Kissing or pointing to it is a sunnah of Nabi Muhammad (PBUH). It is considered a stone from Paradise and will testify on the Day of Judgment for those who touched it with sincerity.
The Hajar Aswad is located at the eastern corner of the Kabah, marked by a green light. During peak times, kissing or touching the stone is extremely difficult due to crowds. It is sunnah to kiss it if possible, touch it, or simply point toward it and say 'Allahu Akbar' from a distance. Each tawaf circuit begins and ends at the Hajar Aswad line.