Forts or follies? Trio of Napoleonic fortresses kitted out as luxury hotels are for sale near Portsmouth for £11m

A set of unique properties have gone on the market for someone who truly wants to get away from it all — three forts floating in the Solent between Portsmouth and the Isle of Wight.

Living and working in a densely populated capital city means most of us will one day crave a life away from noise and people and this trio of luxury fortresses — on sale for £11million as a set — provide exactly that.

Originally built to repel invasion by Napoleon, No Man’s Fort, Spitbank Fort and Horse Sand Fort were built between 1867 and 1880.

Over a mile from land, and only reachable by boat or helicopter, two of the three forts are currently used as luxury hotels while the third is currently being renovated.

No Man’s Fort, for sale for £5million, is run as a hotel and even boasts its own pub, The Lord Nelson.

It can sleep 44 guests in 23 suites and has room to host more than 200 people for parties, and also features a cabaret bar, a spa, rooftop hot tubs and even a laser hunt area, provided fun and games in the warren of tunnels around the fort.

Horse Sand Fort, for sale at a relative bargain of £1million, is being converted into a museum, while Spitbank Fort, also £5million, is a little smaller and is also operating as a hotel, this one with nine suites.

When they were built the forts were nicknamed Palmerston’s Follies after Lord Palmerston, the prime minister who commissioned them.

He insisted they were fitted with a series of 35-ton cannon at a cost of £462,500, or over £43million at today’s prices, for just one fort.

Palmerston believed that Napoleon III was set to invade England, but his fears were unfounded and the buildings were so costly and embarrassing that the fortresses had to be put to some use.

They provided temporary barracks for soldiers but weren’t used in anger until the Second World War, when anti-submarine concrete blocks were laid between them, leaving a narrow strait that only friendly ships knew about.

After the war, the Ministry of Defence realised that the nature of war had changed and they were decommissioned in 1956.

The forts were bought and converted by bed impresario Mike Clare, founder of Dreams, who sold the company for £200million in 2008 and set about spending the proceeds on his passion for unusual property.

He supervised the conversion of the forts, where mod cons and luxury accommodation were installed while retaining the essential character of the forbidding looking fortresses.

Clare is also selling a 15th-century Scottish castle near John 0’Groats, for around £3.9million.

It was extended in the mid-19th century by Scottish architect David Bryce and extensively refurbished and renovated over the last few years.

This, too, is currently being run as a luxury hotel set in 30 acres of grounds.

Henry Jackson, partner at Knight Frank, says: “Solent Forts and Ackergill Tower, each one unique, will provide an incoming purchaser with the exciting opportunity and privilege to own property with such exceptional heritage and history.

“There is considerable potential for an incoming purchaser to build on Mr Clare’s hard work and legacy. These businesses are yet to mature and there is significant scope for growth and development of these enterprises.”

The Solent Forts and Ackergill Tower are for sale with a total price of £14.9million, or available separately, with Knight Frank.