The Ka'ba is a cubical structure located at the center of Masjid al-Haram in Mecca. The Baqara verse, revealed to the Prophet Muhammad, established the Ka'ba as the direction (qibla) towards which Muslims must address their five daily prayers, and as the destination of annual pilgrimage, or hajj, required once in the lifetime of every Muslim. Each year, worshippers gather in the courtyard of Masjid al-Haram and encircle the Ka'ba seven times (tawaf), during which they kiss and touch the Black Stone (al-Hajar al-Aswad), a Muslim object of veneration embedded in the eastern corner of the Ka'ba. As it stands today, the cubical structure is fifteen meters tall and measures ten and a half meters by twelve meters on the exterior. It is oriented such that its four corners align roughly with north, south, east and west.

The structure predates Islam and is believed to have been first built by the Prophet Abraham and his son Ismail, although there are no archaeological findings to support this argument. It is known, however, that the pre-Islamic Ka'ba was rebuilt several times by the tribes ruling Mecca, who used it to house sacred objects, including the Black Stone. During the lifetime of Prophet Muhammad, the Quraysh tribe rebuilt the Ka'ba with alternating courses of stone and wood. The inner space was divided into two rooms, one of which housed the Black Stone. The interior walls were decorated with paintings of Abraham, Mary, Jesus, angels, prophets and trees; and the exterior was covered with the habrat cloth from Yemen.

During the conflict between Ibn Zubayr, ruler of Mecca, and Umayyad Caliph Mu'awiyah, the Ka'ba was set to fire. The Black Stone broke into three pieces and its parts were reassembled with silver by Ibn Zubayr. Ibn Zubayr also ordered the rebuilding of the Ka'ba in stone, in accordance with its original dimensions believed to be set by Abraham, and paved the open space around it. The shrine at this time had two doors and a wooden staircase for roof access. In 692, after taking over Mecca, Umayyad Caliph Abdul Malik bin demolished the Ka'ba and rebuilt it based on the Qurayshi version.

The Abbasid Caliphs contributed to the design of the Ka'ba by covering it with the kiswa, a black cloth brought from Tanis in Egypt. The kiswa comprised of eight curtains (a pair on each side of the cube) embroidered with gold calligraphy expressing the Muslim shahada, or oath, "There is no God but Allah and Muhammed is the Prophet of Allah."

Following Mamluk rule of the Hijaz, which lasted from 1269 to 1517, Mecca came under the control of the Ottoman Sultans. In 1553, Sultan Süleyman I (1520-1566) renovated the roof of the Ka'ba and ordered the wooden ceiling painted with golden calligraphy and floral patterns. Damaged in a flood in 1611, the Ka'ba was rebuilt once again by Sultan Murad IV (1623-1640) in 1629. The new foundation was laid according to Abraham's plan, while the upper structure was built with large granite blocks resting on a twenty-five centimeters high marble base. Three columns were built to support the roof on the inside; they were covered with golden decorations. Silver and golden lamps were suspended from the ceiling. At this time, the silver door offered by Sultan Süleyman I was placed off-center on the northeast wall, two meters above ground level. The Ka'ba was then covered with two kiswas, a red cloth covered with a black one, that were annually replaced.

On the southwest side of the Ka'ba is a semi-circular wall about one and a quarter meters tall, which represents its border (al-hatim) as built by Abraham. The Black Stone is embedded in the eastern corner, one and a half meters above the ground. During the first Saudi extension to Masjid al-Haram in 1976, the interior of the Ka'ba was decorated with gold geometric motifs and inscribed with Quranic verses.

Sources:

Al-Hariri-Rifai, Mokhless. 1990. The Heritage of the Kingdom of Saudi Arabia. Singapore: Eurasia Press, 200-212.

Creswell, K.A.C. 1989. A Short Account of Early Muslim Architecture. Aldershot: Scholar Press, 3-4.

Damluji, Salma Samar (ed). 1998. The Architecture of the Holy Mosque Makkah. London: Hazar Publishing Limited.