Published: 10:27, 25 February 2020
| Updated: 10:50, 25 February 2020
But now striking images show what the decaying structures could look like if they were converted into a luxury glamping retreat.
The pictures reveal the armed towers decorated with fairy lights and tents - with guests travelling around the forts via bridges.
Barratt Homes are imagining what historical buildings which have been abandoned could be like if brought back to life. No plans have actually been lodged.
Other ideas include Aldwych Tube Station in London rendered as an exclusive underground bar and restaurant - and the Point of Ayr lighthouse in Wales reimagined as a remote wellness spa harnessing renewable energy.
A spokesperson for the company said: "Here at Barratt Homes, we love imagining how interesting buildings could look.
"Regenerating disused areas and building communities is a big part of what we do."
Businessman David Cooper hoped to convert the rusting Second World War defences into a £1,000-per-night luxury hotel equipped with a helipad.
He said he thought he achieved this when he was contacted in 2018 by a man acting on behalf of a potential investor from Qatar, who said his client was prepared to pay between £50m and £100m to convert the forts.
But the plans hit a stumbling block after the deal with Middle Eastern investors fell through.
Instantly recognisable, the forts, which were built in 1943 and designed by Guy Maunsell, feature prominently on the horizon off the Kent coast.
Decommissioned in the 1950s, they are not technically owned by anyone - but they are on the Crown Estate’s land.
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