A wooden door covered in more than 50 carvings from soldiers garrisoned there from the wars of the French Revolution through the mid-19th century has been discovered at Dover Castle. Graffiti include initials, surnames, dates, a large single-masted sailing ship and nine men hanging from gallows.

First built shortly after 1066 to defend the Strait of Dover, the shortest sea crossing between England and mainland Europe and therefore an inestimably valuable strategic position, Dover Castle took its permanent form under Henry II. The great keep, towers, inner and outer baileys were completed by 1188. St. John’s Tower was added under Henry III after 1217.

The castle’s fortunes declined in the Civil War period (1642-5), and it began to be used as a prison for captured French and Spanish soldiers in the wars of the late 17th and early 18th centuries. They passed the time carving graffiti on the walls. Dover Castle was revived as a defensive fortress in the Georgian period as tensions rose between Britain and France.

A new construction program restored the crumbling buildings and erected new barracks to house infantrymen in the 1750s. Come the wars of the French Revolution and Napoleon, military engineers completely redesigned the outer defenses to protect the castle from modern artillery and converted the Great Tower into a massive magazine for gunpowder, shot, shells and other supplies. Thousands of soldiers were garrisoned there.

The door with the carvings was originally on an upper floor of St. John’s Tower. During Dover Castle’s revival, it was guarded at all times by six to 12 men, one or two of them manning the top room repurposed as a watchtower because of its a commanding view of the exposed northern flank of the castle. The guards were armed with knives, perhaps bayonets, and they put their sharpened ends to good use decorating the old door.

The plank door was rediscovered several years ago. It had long been inaccessible without using a ladder to reach the base of a spiral staircase. Covered in several thick coats of paint, the graffiti were not immediately evident. It was only when the door was removed for conservation and the old paint layers stripped that the engraved treasure they were concealing was revealed.

The St John’s Tower door contains around 50 pieces of carved graffiti. These include: three dates: 1789, the date of the French Revolution; 1798, a period of rebuilding in the castle; and 1855, when changes were planned to the tower. There are also many sets of people’s initials and two surnames: Downam and Hopper/Hooper. At least nine contain gruesome illustrations of hangings, a strange and macabre repetition, including one example where a man wears a military uniform and a bicorne hat. It is possible that this could be a depiction of a real hanging, as hangings were known to take place in Dover and did serve as morbid entertainment, or perhaps even a representation of Napoleon himself. Also present is a detailed and accurate carving of single-masted sailing ship, most likely an 8-gun cutter which was a fast vessel used by the Royal Navy, the Revenue Service, smugglers and privateers. Another curious symbol which depicts a glass or chalice for wine, surmounted by an elaborated cross, may be a representation of Christian holy communion.

The door was removed from its original location for conservation and stabilization. Old coats of paint, added after the graffiti was carved, were removed. The wood of the door was cleaned and treated for long-term preservation. It will go on display in July at Dover Castle’s new exhibition, Dover Under Siege. In addition to viewing the door, visitors to the exhibition will have the chance to walk the castle’s northern defenses, casements and its medieval and Georgian underground tunnels.