The wreck of a pre-First World War German battleship, sunk off the coast of Kent in 1878, has been added to England's National Heritage List.
The Cheriton Road Cemetary in Folkestone, where the bodies of 284 men who died when the ship went down are interred, has also been listed at Grade II.
The SMS Grosser Kurfurst sunk in the English Channel in May 1878 as it was preparing for its annual summer training sessions after it was accidentally rammed by another German warship, the Konig Wilhelm, which was turning to avoid colliding with a pair of sailing ships.
The Konig Wilhelm had a strengthened ram bow designed to sink enemy ships which ripped away armour plating on the SMS Grosser Kurfurst, leaving a huge hole on its side. It sank rapidly.
SMS Grosser Kurfurst was one of only three Preussen-class ironclad warships authorised under a naval programme of 1867, approved by the Reichstag to strengthen the North German Federal Navy. Originally designed to carry armaments, it was modified during construction to mount a pair of revolving twin-gun turrets.
The ironclad ship was built during an experimental period in naval warfare when they moved from wooden to armoured ships.
"The SMS Grosser Kurfurst is important as the only non-Royal Naval warship recorded as wrecked in English waters for the period 1860-1913," Duncan Wilson, Chief Executive of Historic England, explained in a statement.
"The listing of the associated memorial in Folkestone with its German inscription is a poignant reminder of the loss of nearly 300 crewmen on board. It is right that we continue to remember them," he added.
Being added to the National Heritage List means recreational divers have permission to dive there but the ship's content are given a level of protection.
"I hope that the increased protection for both sites will ensure that the ingenuity of the early ironclad ships and their influence on modern navy vessels is not forgotten," Nigel Huddleston, Heritage Minister also said.