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:Linderhof is the smallest of the three palaces built by King Ludwig II of Bavaria and the only one which he lived to see completed.
Ludwig II, who was crowned king in 1864, began his building activities in 1867-1868 by redesigning his rooms in the Munich Residenz and laying the foundation stone of Neuschwanstein Castle. In 1868 he was already making his first plans for Linderhof. However, neither the palace modelled on Versailles that was to be sited on the floor of the valley nor the large Byzantine palace envisaged by Ludwig II were ever built.
Instead, the new building developed around the forester's house belonging to his father Maximilian II, which was located in the open space in front of the present palace and was used by the king when crown prince on hunting expeditions with his father.