Formerly a tidal island, Cornet Rock was first fortified as a castle between 1206 and 1256, following the division of the Duchy of Normandy in 1204. In 1339 when a French force captured the island and occupied it for several years, Cornet was besieged and captured, and the garrison massacred. With the advent of cannon and gunpowder, the castle was remodelled between 1545 and 1548. Prof. John Le Patourel, in The Building of Castle Cornet mentions that in 1566, iron and hammers were taken to 'Creavissham' (i.e. Crevichon), and that island quarried for the castle.
Castle Cornet served as official residence of the Governor of Guernsey until 1672 when the keep was catastrophically destroyed. A bolt of lightning struck the magazine of the castle, destroying the keep and a number of living quarters. The Governor at the time was Lord Hatton. His mother, wife and a number of members of staff were killed in the explosion. It became integrated into the breakwater after the period of the Napoleonic Wars. Along the breakwater, a pond for toy yachts was constructed in 1887 for Queen Victoria's Diamond Jubilee, which served as a seaplane base during World War I. In World War II, it became occupied by a small group of German troops. It was presented to the people of Guernsey in 1945 by the Crown.
The castle incorporates today several museums, like castle museum, maritime museum and Royal Guernsey Militia museum.
References:The Temple of Edfu is one of the best preserved ancient shrines in Egypt. It was built in the Ptolemaic Kingdom between 237 and 57 BC.
Edfu was one of several temples built during the Ptolemaic Kingdom, including the Dendera Temple complex, Esna, the Temple of Kom Ombo, and Philae. Its size reflects the relative prosperity of the time. The present temple initially consisted of a pillared hall, two transverse halls, and a barque sanctuary surrounded by chapels. The building was started during the reign of Ptolemy III Euergetes and completed in 57 BC under Ptolemy XII Auletes. It was built on the site of an earlier, smaller temple also dedicated to Horus, although the previous structure was oriented east–west rather than north–south as in the present site.