The only First World War anti-aircraft gun to be restored to working condition will fire again will be unveiled at Dover Castle this weekend.

The gun has been restored by English Heritage and will take pride of place at the 1915-Dover at War event on Saturday and Sunday, August 1 to 2.

A team of trained volunteers will create a special re-enactment and fire the gun 100 years after it was originally used.

Dover was officially designated as a Fortress during the First World War, containing a garrison and training camps for more than 10,000 men, and this £490,000 project has recruited local volunteers to help tell the story of this important chapter in the town’s history.

Paul Pattison, senior historian at Dover Castle, said: “Our project is telling the whole story of Dover during the First World War.

“Planes hadn’t been around very long and air warfare was becoming a reality. They hadn’t experienced it before so there was a rush to develop purpose-made weapons to counter this threat.”

An identical gun at Langdon Battery hit a Zeppelin and repelled a German raid, which shows how vital it was to Dover’s defences.

Alongside the gun, there is a restored building where military and naval forces would have been stationed.

The first floor is the Fire Command Post where the former office has been transformed into an exhibition, documenting the changes at the building itself and how Dover as a town was affected by the war - by air raids, and by the tens of thousands of men and women passing through the town.

People from outside Dover even had to obtain passes to visit friends or relatives in the town.

The Fire Command Post also gives visitors an idea of what it was like to look out across the Channel, trying to spot if specks in the distance were British or German ships.

Mr Pattison said: “There’s an atmosphere in here – it really does feel like you are in 1915.

“Someone would be here 24 hours a day in the most dangerous seaway in the world.”

Upstairs, in the Signalling Post Room, is another row of windows looking out across the sea.

The Navy would be looking out for their own ships returning and keeping an eye out for enemies.

Here visitors can eavesdrop on a wartime conversation by picking up one of the telephones.

They can communicate to each other through pipes and see where the Naval ratings would have eaten and slept.

A group of volunteers will create a re-enactment and fire the gun (without real shells) on Saturday and Sunday at 1pm. They will do this every week at the same time.

This has been made possible by a grant of £272,600 from the Heritage Lottery Fund (HLF) and aided by support from The Friends of Dover Castle.

The event is open 10am until 5pm, and there will be Edwardian music, cavalry and falconry displays as well as a replica biplane.

Adult tickets are £18, children are £10.80.