Monreale

Monreale lies above Palermo, on the slope of Monte Caputo, overlooking the very fertile valley called "La Conca d'oro" (the Golden Shell), famed for its orange, olive and almond trees.  Surveying Palermo and the Conca D’Oro from its panoramic hilltop position, Monreale would be a fairly non-descript town save for one of the world’s most stunning architectural treasures: the Duomo.

When the Arabs took control of Palermo in 831, they transformed the cathedral into a mosque and banished the Bishop of Palermo from town.  The role of the cathedral was assigned to a modest little church, Aghia Kiriaki, in the village nearby which was later called Monreale.  Some 240 years later, in 1072, the Normans drove the Arabs from Sicily, establishing Palermo as their capital and re-consecrating the cathedral.  In 1174 King William II ordered the construction of a new church in Monreale, dedicated to the Virgin Mary.  Enlightened, tolerant and appreciative of many aspects of North African and middle-eastern culture and art, William II employed the very best Arabic, Byzantine and Norman craftsmen to work on the cathedral. The result is a fascinating fusion of architectural styles, artistic traditions and religious symbolism.

It is, however, the large extent of the glass mosaics that makes this church so splendid.  With the exception of a high dado, made of marble slabs with bands of mosaic between them, the whole interior surface of the walls, including soffits and jambs of all the arches, is covered with minute mosaic-pictures in bright colors on a gold background.  The geometrically patterned marble floor, in-laid with Middle-Eastern mosaics, supports two lines of granite Corinthian columns that delineate the wide, lofty, wooden-roofed nave.  Lancet arches leap from column to column drawing the eye to the window-punctured clerestory and its astonishing display of art.

Outside the Cathedral, adjoining its south side is another artistic and architectonic masterpiece: the cloisters. Built in 1200 as part of the Cathedral abbey, the cloisters comprise 108 pairs of marble columns, a covered arcade of Arabic arches and a central quad. Every other pair of columns is decorated with unique mosaic patterns, no two are the same, each topped by a floral capital.  The overall effect is one of not quite perfect symmetry.

Wikipedia has some excellent images of the mosaics, particularly those near the bottom of the article which can be expanded, or google Monreale and then select images.