Barricaded off by ugly metal fencing and left in a crumbling state of disrepair, neglected Canterbury Castle has seemingly been long-forgotten.

But after more than two years of being shut to the public, one of the city's most historical structures is scheduled to reopen in 2021.

It is hoped the castle, which is closed due to health and safety fears, can be a "sparkling jewel in Canterbury's heritage crown" as it becomes a key tourist attraction and history centre for learning.

WATCH: A historic Kent castle could reopen

Despite there being no sign of action on site, the council says work is underway behind the scenes and a newly established friends group also has its eyes set on refurbishment.

Many residents have been left disappointed by its current sorry state.

Kieran Monk said on Facebook: "Needs a good revamp and some investment.

"Why the council has let it get into this state is ludicrous."

Claire Cardy added: "It should definitely be restored and reopened.

"It's part of Canterbury's heritage, and when you think how much tourism is worth to the city, it would be more than worth it.

"Only yesterday a couple of tourists asked me if they could visit the castle."

Others suggested turning the castle into a wedding venue or a location for hosting medieval fetes, which would help recoup the repair work costs.

Karen Isaac commented: "It survived all the past, including the Victorians basically using it as a shed for coal, so the least this era can do is continue to make it safe and protected."

The Friends of Canterbury Castle group, which includes new council leader Rob Thomas, is now busy working towards a 2021 reopening.

Member and Barton ward councillor Connie Nolan says masonry needs to be stabilised and a new pathway installed.

"The castle should be a sparkling jewel in Canterbury's heritage crown but is outshone by the Cathedral and St Augustine's Abbey.

"The castle should be a sparkling jewel in Canterbury's heritage crown but is outshone by the Cathedral and St Augustine's Abbey" - Cllr Connie Nolan

"We can make much more of it and have a world heritage trail leading tourists to the castle.

"We have a date to work to there is a hive of activity."

Council spokesman Rob Davies says there are obstacles yet to overcome.

"One important factor is the need to secure Historic England (HE) approval for any work, as the castle is a Scheduled Ancient Monument," he said.

"We have already approached HE about this and are awaiting a reply, but this means the timetable for any work is out of our hands.

"We'll be taking a report through our committee process in the next few months to obtain councillor agreement on the final proposals and budget."

After victory at the Battle of Hastings in 1066, William the Conqueror marched to Canterbury, and the very first Norman castle in England was built at the site we now know as Dane John Gardens.

The distinctive mound in Dane John may be the motte from the original wooden castle - which itself was replaced by the present stone structure during the reign of Henry I.

As one of Kent’s three original royal castles, the keep, which was about 80ft high, was the fifth largest in England. It later became a jail.

Taken by the French without struggle in 1216, the keep was left in ruins in 1609 having never seen a battle.

It was used for storing gas in the 19th century and went on to continue falling into a state of disrepair.

The city council owns the site.

Entry to the castle was free to the public until its closure in 2017.

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