Dome of the Rock, Jerusalem

The impressive effect of the Dome of the Rock results from the combination of fine proportions and sumptuous decoration with an apparently simple ground-plan consisting of three concentric elements. Round the rock is a ring of piers and columns supporting the dome; a broad ambulatory separates this ring from an octagon, also formed by piers and columns; and this in turn is separated from the octagonal outer walls by a narrow ambulatory.K. A. C. Creswell discovered how the proportions of the building were worked out. Two squares were set out within the inner circle, one at an angle of 45 degrees to the other. If the sides of these squares were produced in both directions they met at eight points - the piers in the octagon between the two ambulatories. If the sides of the octagon were also produced in both directions they too met at eight points, forming two larger squares with sides parallel to the inner squares. If an outer circle was then described round the two larger squares and the sides of the inner octagon were extended outwards until they intersected this circle a larger octagon was formed, the line of the outer walls.The diameter of the octagon is 54.8m/180ft, and each side of it has an external length of 2.5m/67ft (internal length 19.2m/63ft). The dome has a diameter of 23.7m/78ft and rises to 33m/108ft above the ground; it is topped by a crescent 3.6m/12ft high.The exterior walls of the octagon were faced with superb faience tiles in the reign of Suleiman the Magnificent (1520-66); the elegant dome of gilded aluminum dates from the restoration of 1958-64.Four doors, clad with copper by Qaitbay (1468-96), lead into the interior, which is exquisitely decorated, with richly ornamented wooden ceilings over the two ambulatories, magnificent marble piers and columns topped by antique capitals, two-colored round-headed arches over the inner colonnade, stained glass windows filtering the light, mosaics on a gold ground in the inner rotunda and the ambulatories and luxuriant ornament on the dome. There is a striking contrast between the brightly colored tiles which emphasize the solidity of the outer structure and the mysteriously shimmering mosaics in the interior.In the center of the inner rotunda, rising to a height of 1.25-2m/4-6.5ft above the floor, is Es- Sakhra, the Holy Rock, over which the Jews' altar for burnt offerings may have stood. Just under 18m/59ft long by 13.25m/43ft across, it is surrounded by a grille installed by the Crusaders in the 12th century to prevent relic-collectors from breaking off pieces of the stone. The best view of the Holy Rock is to be had from the high bench beside the northwest gate in the grille. In Jewish belief the rock marks the spot where Abraham prepared to sacrifice Isaac, while the Muslims believe that it was from here that Mohammed ascended into heaven. Under the rock is a cave, known to Muslims as Bir el-Arwah ("Well of Souls"), where it is believed that the souls of the dead gather to pray.