A giant hotel and leisure centre are planned for a historic site in Kent as part of an ambitious £100 million pound renovation project.

Shops and cafes are also proposed for the Citadel at Dover's Western Heights, which dates back to the 1700s.

It is hoped the renovation will be completed within the next six to eight years, with long-term plans also including a cycle track.

A public consultation for the brownfield site - originally a defence base to stop invasion by Napoleon’s forces and later a youth detention centre - is planned in the next six months.

The organisation behind the development is the landowner, Dover Citadel Ltd.

One of the directors, David de Min, said: “We want to unlock this historical asset.

“It will be the biggest change in 70 years when the prison service took it over.

“This is a vast area of 33 acres with 54 buildings and we want to use it as well as possible.”

Planning permission was granted this spring by Dover District Council for the first phase of the scheme, which could see six small businesses moving into the casemates within the fort, or one single large business.

A courtyard with seating is planned, while windows, toilets, heating and new lighting would be added.

The work involves minimal physical alterations to the current buildings.

That part of the project was further pushed forward by a £1 million grant from the government’s Getting Building Fund grants scheme.

An artist’s impression of the proposed scheme has been drawn up by Hythe-based architect firm Hollaway, and was released earlier this year.

It gave an idea of what the project could look like when finished, and included a potential gallery, workshop and market in the renovated casemates, with a food truck in the courtyard.

Planning applications are now expected shortly for the proposed hotel of 200 to 250 rooms, a leisure centre and cycle track.

End-to-end the project is valued at £80 million to £100 million, bosses say.

The area is already home to Citadel Studios, which has regularly been used for shooting TV and film productions.

It was used for some scenes of the TV crime drama Whitstable Pearl, which came out last year.

Videos for the electronic music group Jungles have also been filmed there.

The Citadel was also a backdrop in Pistol, the Danny Boyle TV show based on the life of Sex Pistols guitarist Steve Jones. That was on top of location filming at Dover seafront, Deal town centre and The Grand in Folkestone in April 2021.

The Citadel, one of the highest points in Dover, has disused buildings including prison wings, a guard room, a gymnasium and a canteen.

It also has Second World War bunkers, a network of underground tunnels, officers’ quarter, workshop armoury, pump house and barrack huts.

The first recorded permanent fortifications to be established on the Citadel date from 1770.

From 1804 these were vastly developed to prepare for the threat of invasion from Napoleon Bonaparte’s forces from across the Channel.

The land was in continuous military occupation over 170 years, with the fortification representing one of the largest and most elaborate surviving examples of its kind for the 19th century in England.

It was used for barracks during both world wars.

The Citadel was transferred to the Prisons Commission in 1954 to become a Borstal and Young Offenders Institution.

Most recently the site was an immigration detention centre until November 2015.

Dover Citadel Ltd bought the land from the Ministry of Justice in 2020.

A casemate is a fortified gun emplacement or armored structure from which guns are fired, in a fortification, warship, or armoured fighting vehicle.