over Castle is situated at the shortest sea crossing of English Channel. This has made it one of the most important defensive sites in Britain. The site dates back to the Iron Age and has a Roman lighthouse and an Anglo-Saxon church. As soon as William the Conqueror landed in England he made sure that he had control of the castle at Dover. Henry II added much of the defences now visible at the site including the keep which was built between 1170 and 1180. The keep which still stands is surrounded by a double ring of walls and consists of three floors and walls that vary between 17 and 21 feet thick. Several small rooms are built into the thickness of the walls. The keep has three staircase, one in the forebuilding and the other two in opposite corners.In 1216 Dover Castle was besieged by Prince Louis of France. King John left Hubert de Burgh in charge at Dover and even though the French managed to breach the defences by undermining the north gate, de Burgh's forces beat back the attack and Prince Louis called a truce. The truce was short lived as John died soon after and Louis again attempted to take the castle. Louis was eventually defeated by Hubert de Burgh.
Hubert de Burgh with Henry III's backing rebuilt the damaged castle removing areas of weakness that had been exposed during the siege. This included the construction of an inner wall around the keep.
Of interest now are the newly opened 'Secret War Tunnels' that were dug into the white cliffs of Dover and used during World War II as a hospital and for strategic planning. Recently English Heritage has decorated the inside of the keep to show how it may have looked in medieval times.
