But when he and his wife, Molly, began looking for a home, they found that the traditional retirement hot spots in the Cotswolds or seaside towns on the south coast were not their scene either.

After months scouring the country, Ian, 77, and Molly, 70, are living in a 2,000sq ft flat in a modern glass development overlooking the River Thames.

The couple sold their “very large” house in West Sussex in 2003, and bought a three-bed flat in Putney. They are reluctant to say how much they paid, but a similar flat in the same block is for sale for £1.7m.

“We looked everywhere but couldn’t find anything that suited,” says Molly. “We’re not village-type people. I don’t care to arrange the church flowers.”

Ian says: “People used to look horrified when we said we were moving to London. I mean, most people imagine retiring to the countryside.”

Now that they have put up roller blinds in the glass- fronted flat “to feel less like goldfish”, and soundproofed the wall “so you can no longer hear the neighbour snoring”, the Brookes have taken London life in their stride.

“We are delighted,” says Molly. “All the shops are nearby, as are good hospitals. I never really liked gardening, so getting rid of the garden was good. We have three terraces so we can go outside. I never feel cooped up.”

More importantly, they feel safe: “Whenever we went on holiday at our old house, I was worried that the place would be burgled or vandalised,” says Ian. “But now we just say goodbye to Richard, the porter, and don’t worry at all.”

The Brookes are part of a new wave of elderly buyers who are choosing to retire to London. By 2007 the number of people aged over 65 in Britain will exceed those under 16 for the first time in history, according to research by the think tank Demos. And by 2025, more than a third of the UK’s population will be over 55.

It’s a fact that developers are increasingly aware of, as they compete for a share of the “grey” market. A quarter of the properties that estate agency DTZ Residential has sold this year in central London have been to people of retirement age. At Vincent Square in Westminster, where two-bed flats start at £485,000, more than half the properties were bought by over-55s.

Mike Bickerton, associate director at DTZ Residential says: “They tend to be couples who are downsizing, but want the excitement of London.”

Emma Soames, the editor of Saga magazine, expects the trend to continue. “There are museums, shops and theatres on the doorstep,” she says. “Just because you are retiring, you do not have to vegetate in remote parts of the country.”

Carolyn McQuitty, sales and marketing director at Pegasus, a retirement developer, says: “It is very easy for those aged 60 and over to follow the retirement trend and move to the country or seaside in search of what is often thought of as the ‘ideal retirement’. However, a growing number of people, who used to live in the city before retiring, are moving back to London.”

It was the culture of the capital that attracted Paul and Ann Coggle. They lived in London in their early twenties and spent 30 years in Canterbury, where Paul, 67, was a lecturer in German at the University of Kent. They are selling their five-bed, £615,000 house and have bought a Victorian terraced house within walking distance of Waterloo.

“We wouldn’t live anywhere else,” says Paul. “We can walk everywhere we want to and it is much easier to travel abroad.”

Richard Donnell, a director of Hometrack, a property consultancy, agrees there is a noticeable trend of buyers trading down to city centres.

“It will continue to be a growing trend,” he says, “for those that can afford it. The baby boomer generation will also make an impact on the retirement market.”

“We’re at the vanguard,” says Brooke. “Our grandchildren think we are ‘cool’.”

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