Dover Castle in Kent is known as the “key to England” for its defensive importance in the last 2 millennia of history. The medieval fortress dates back to the eleventh century and is the largest and most important castle in England. The site may have been fortified already during the Iron Age, long before the Romans attacked Britain (in 43 AD with the emperor Claudius). Such an ancient date is suggested by the form of the embankments unusual for a medieval castle. The archaeological excavations suggest anthropic activities in the area of the castle, but they have not yet given the certainty that these were then concluded with the construction of a sort of fortification.
The strategic position of the castle, right in front of the European continent, has made it the main point of arrival for all the peoples who have tried to invade the British Isles. The castle’s last defensive function dates back to World War II, when the British built several additional tunnels to those built at the beginning of the nineteenth century by General William Twiss for the Napoleonic Wars. The multi-level labyrinth cut into the soft white chalk was built to hold 2,000 troops, but Napoleon never did arrive, and the tunnels were abandoned. Then World War II came around and they were enlisted as a strategic air raid shelter as well as a hospital and command center. You can still find the old operating theater there.
Already in Roman times, however, the site was used for its strategic location, and it is in fact one of the oldest buildings in England.
At the beginning of his first attempt to conquer Britain, in 55 BC, Julius Caesar initially attempted to land in Dubris (Dover), whose natural harbor is presumably identified by one of his officiers, Gaius Volusenus. When the Roman fleet came in sight of the shore, unexpectedly found an army of British perched on the hills overlooking the port, whose javelins could easily reach the Roman ships. After waiting in Dubris “until the ninth hour” (about 3pm) waiting for the supply vessels, Caesar ordered the soldiers to act on their own initiative, sailing for about seven miles along the coast and finally finding a free beach.
During the various waves of Roman invasion, continued throughout the first century AD, two lighthouses were built in Dubris, functional to have a point of reference in the port closest to the European continent. The hypotheses of dating range from an interval of 50 years AD to 138 AD, although it is widely believed that buildings were built within the first century.
Of the two Roman lighthouses today only the one adjacent to the castle of Dover remains, which retains for the most part the original appearance of over 2 millennia ago. The building is about 24 meters high and has been adapted as a bell tower of the church of Saint Mary in Castro, the church inside the castle itself. Dover Castle is known as a major military center for England, but it’s just as significant now for having one of the few surviving Roman lighthouses. The Dubris lighthouse is now considered the oldest building in England, along with the Temple of Claudius at Colchester. They are the oldest in England, but not in Britain, where there are numerous testimonies of older structures in Scotland and its islands.