11th-century fortifications

royal residence at Windsor in Berkshire, England, UK

medieval castle in Warwickshire, England, UK

castle in Cardiff, Wales

Grade I listed castle in Winchester, United Kingdom

ruined castle in Fotheringhay, Northamptonshire, England, UK

castle in Castleton, Derbyshire, England, UK

Grade I listed historic house museum in Conisbrough, Doncaster, South Yorkshire, England, UK

medieval fortress in Spain

castle in West Yorkshire, England, UK

castle in Wallingford, Oxfordshire, England, UK

Grade I listed castle in Dudley, United Kingdom

Grade I listed castle in Prudhoe, Northumberland, England, UK

castle ruin in Shathah District, Syria

Gibelacar (), also known by its original Arabic name Hisn Ibn Akkar () or its modern Arabic name '''Qal'at Akkar''' (), is a fortress in the village of Akkar al-Atiqa in the Akkar Governorate in northern Lebanon. The fortress dates back to the Fatimid era in the early 11th century. It was captured and utilized by the Crusaders in the early 12th century until it was captured and strengthened by the Mamluks in the late 13th century. It became the headquarters of the Sayfa clan, whose members, chief among them Yusuf Pasha, served as the governors and tax farmers of the Tripoli Eyalet and its sanj

buildings on two neighbouring sites in London

castle in France

medieval castle in Powys, Wales, UK

castle in Herefordshire, England, UK

Norman castle in Bristol

castle in England

castle in Suffolk, England, UK

Grade I listed castle in Staffordshire, England, UK

castle in Lower Austria

The Harzburg, also called Große Harzburg ("Great Harz Castle"), is a former imperial castle, situated on the northwestern edge of the Harz mountain range overlooking the spa resort of Bad Harzburg in Goslar District in the state of Lower Saxony, Germany. It was erected from 1065 to 1068 at the behest of King Henry IV of Germany, slighted during the Saxon Rebellion in 1073-75, and a century later rebuilt under Emperor Frederick Barbarossa and his Welf successor Otto IV, who died here in 1218.

fort in Santiago de Compostela, Spain