The Ka'aba is an oblong stone building located approximately in the center of the quadrangle of the Grand Mosque in the Holy City of Makkah. The front and back walls are 40 feet in length; the side walls are 35 feet long; the height of the walls is 50 feet.
Set in a silver surround in the east corner of the Ka'aba, some four feet above ground level, is the Black Stone. This sacred Stone, the focal point of the Hajj, is the only remnant of the shrine which Abraham built when it was given to Abraham by the angel Gabriel.
The Stone (which may be of meteoric origin) is believed to go back still further, to the time of the first man, Adam.