A hidden door scribed with centuries-old soldiers’ graffiti has been discovered at a world-famous Kent castle.

Historians found the Georgian piece at Dover Castle decorated with the initials of servicemen along with depictions of hangings and a detailed carving of a sailing ship.

The door was found in St John’s Tower and dates back to about the 1790s - a time when a Napoleonic invasion of England was a real threat.

English Heritage’s senior properties historian Paul Pattison says the markings provide unique insight into the mindset of troops during the period.

“Scaling a ladder to the upper floor of St John’s Tower and seeing these remarkable carvings on the door was an astonishing discovery for us,” said Mr Pattison.

“This graffiti gives a unique glimpse into the minds of these soldiers, especially during such a charged period of time.

“As a result of the impending threat of war from across the Channel, Dover was a hive of activity with ships filling the harbour and coloured military uniforms a constant presence in the castle and town.

“What makes this door such an extraordinary object is that it is a rare and precious example of the ordinary person making their mark; whether that be simply for the purpose of killing time or wanting to be remembered.”

The door contains about 50 pieces of carved graffiti.

Among the illustrations are at least nine gruesome illustrations of hangings, including one example where a man wears a military uniform and a bicorne hat.

Experts believe this could be a depiction of a real hanging, as hangings were known to take place in Dover and did serve as morbid entertainment.

Also present is a detailed and accurate carving of a single-masted sailing ship, most likely an eight-gun cutter which was a fast vessel used by the Royal Navy.

After the discovery, the door was removed from St John’s Tower to protect and preserve it for future generations.

It was also conserved by the careful removal of paint layers from the decorative surface of the door, and then the wood was then cleaned, toned and treated.

The artefact will go on public display in July as part of a new exhibit at the world-famous landmark.

‘Dover Castle Under Siege’ will allow visitors to explore the fortress’ northern defences, including the medieval and Georgian underground tunnels.