The Kaaba is the cube-shaped building at the centre of the Grand Mosque — the most sacred structure in Islam. Muslims face toward the Kaaba during prayer, wherever they are in the world. The structure is approximately 13 metres high and draped in a black silk cloth (the kiswah) embroidered with gold Quranic verses, which is renewed annually.
The interior of the Kaaba, which pilgrims rarely enter, contains a bare marble floor, incense burners, and hanging lamps. The rituals of Hajj and Umrah include circling the Kaaba seven times (tawaf) and touching or kissing the Black Stone set into its south-eastern corner if possible — though the crowds during Hajj make this difficult for most pilgrims. The Kaaba has been rebuilt many times over the centuries following floods, fires, and damage; its current form dates substantially from a 1630 reconstruction under the Ottoman Sultan Murad IV.