The Cathedral of Monreale is one of the greatest existent examples of Norman architecture. The construction of Monreale, started in 1172, was approved by Pope Alexander III with a bull on 30 December 1174. Works, including an annexed abbey, were completed only in 1267 and the church consecrated at the presence of Pope Clement IV. In 1178 Pope Lucius III established the archdiocese of Monreale and the abbey church was elevated to the rank of cathedral. The archbishops obtained by the kings of Sicily a wide array of privileges and lands in the whole Italian peninsula. In 1270 Louis IX, King of France, brother of King Charles I of Naples, was buried here.
In 1547-1569 a portico was added to the northern side, designed by Giovanni Domenico Gagini and Fazio Gagini, in Renaissance style, covered by a cross vault and featuring eleven round arches supported by Corinthian columns. In 1559 most of the internal pavement was added.
The church's plan is a mixture of Eastern Rite and Roman Catholic arrangement. The nave is like an Italian basilica, while the large triple-apsed choir is similar to one of the early three-apsed churches, of which so many examples still exist in Syria and elsewhere in the Middle East. It is like two quite different churches put together endwise.
The main internal features are the vast (6,500 m2) glass mosaics, executed in Byzantine style between the late 12th and the mid-13th centuries by both local and Venetians masters.
Since 2015 it is part of the Arab-Norman Palermo and the Cathedral Churches of Cefalù and Monreale UNESCO Heritage site. The church is a national monument of Italy and one of the most important attractions of Sicily.
Kristiansten Fortress was built to protect the city against attack from the east. Construction was finished in 1685. General Johan Caspar von Cicignon, who was chief inspector of kuks fortifications, was responsible for the new town plan of Trondheim after the great fire of 18 April 1681. He also made the plans for the construction of Kristiansten Fortress.
The fortress was built during the period from 1682 to 1684 and strengthened to a complete defence fortification in 1691 by building an advanced post Kristiandsands bastion in the east and in 1695 with the now vanished Møllenberg skanse by the river Nidelven. These fortifications were encircled by a continuous palisade and thereby connected to the fortified city. In 1750 the fortress was modernized with new bastions and casemates to protect against mortar artillery.