In the mid-1980s, an advert regularly appeared in newspapers across the country. It read: “On DHSS? Living in poor conditions? Why not live by the sea in Margate? Pleasant hotel, own key”.

The hotel in question was in Cliftonville - a part of Margate which was once the town’s plush upmarket tourism hub; a pleasure palace for the wealthy middle classes.

In 1984 and 1985, when those adverts appeared, it was reduced to appealing nationwide for the unemployed to come and spend their dole money amid its crumbling, former splendour. How things had changed.

As one veteran Kent MP puts it, the area became dubbed “Dole-on-Sea”.

And it was far from alone.

The actions of that hotel - the long since defunct Roxburgh - prompted others to follow suit; not just in Kent but other coastal towns trying to make the sums of a wealth of legacy guesthouses and hotels add up in an age and destination where few wanted to spend any longer than a day. They would fail.

So how did our seaside towns fall so heavily? Why did the rot set in and, perhaps more significantly, why did it take decades before they would once again spark back into life? For the purposes of this exercise, we’ll focus on perhaps Kent’s two most historic hotspots - Folkestone and Margate.

The key lies in the answer to a simple question: If you had a choice, would you rather splash about in the greeny-brown waters of the English Channel, or North Sea, beneath ominous skies, or the warmer, clearer Mediterranean as you look up at unrelenting blue skies?

The answer is, almost certainly, the latter for the vast majority of us. And that, in a nutshell, is what ripped the very heart out of so many of Kent’s biggest coastal resorts.

After decades of boom - stretching from the 18th century to the mid-20th - a bust was, perhaps, inevitable.

So heavily reliant on tourism - it was the economic backbone of the vast majority - the introduction in the 1960s of the cheap foreign package holiday was like a cancer to our seaside resorts - slowly growing over the next 30 to 40 years and suffocating their economic and social lifeblood.

To fully understand the decline, you need to remind yourself of the history of our key seaside towns.

For the most part they had boomed courtesy of the London holidaymaker. They had benefitted from paddle steamers bringing thousands out of the capital and down the Kent coast for decades and then further capitalised with the coming of the railways.

The riches they reaped saw them expand - attractions, guesthouses, ornate gardens - all designed to pull in the tourists and extract as much money as possible. Entertainment venues sought to pull in off-season crowds.

Yet, for some, the package holiday was the final, lingering, killer blow which had started years before.

“After the First World War,” reflects Alan Taylor, chairman of the Folkestone & District Local History Society, “people didn’t come back to the town in the numbers they once did. So the council invested heavily in a bid to win them back.”

Folkestone, once a powerhouse of domestic tourism, had been a town transformed by the Great War. It had become synonymous with the arrival and departure of troops to the killing fields of France and Belgium. And it had taken in thousands of refugees fleeing northern Europe.

The local authority knew its prosperity hung on tourism so invested heavily after the guns stopped. The Leas Cliff Hall, East Kent Pavilion and the ornamental Kingsnorth Gardens were all created in a bid to lure back the crowds. As well, coincidentally, as the Marine Gardens Pavilion - later to become the town’s La Parisienne nightclub.

And, to a degree, it worked. By the 1930s the crowds were returning in their droves. But then came the Second World War and the town was once again on a war footing.

“There was a post-war boom once it ended,” adds Mr Taylor, 87. “There was extensive bomb damage to the town, but where people hadn't been on holiday for years, the town was crowded.”

Worth noting is that it was in 1948 that Sidney De Haan and his wife moved to the town - buying the Rhodesia Hotel. Concerned at how little custom they had during the winter months, they hatched upon the idea of marketing both their hotel - and then others in Folkestone - as the ideal discount off-season holiday location for older folks. Saga Holidays was born and it made a big difference.

By the early 1950s, not only Folkestone was benefitting, but the likes of Margate and Eastbourne too. Suddenly the seasonal trade on which they relied rolled year-round.

So it was perhaps ironic that another form of holiday would come to threaten Kent seaside towns’ new all-year-round appeal. The cheap foreign package tour.

While Saga was able to pivot and capitalise by offering the same deals but to out-of-season foreign resorts, the likes of Folkestone and Margate were left with a major dilemma.

Explains Alan Taylor: “It became a day trip place. People didn’t want to stay overnight. A lot of the hotels were demolished or converted into flats. It left the town with just a few hotels and far less guesthouses.”

The same was happening elsewhere.

“In Margate,” says Sir Roger Gale, its MP since 1983, “we had a lot of fortnight-holiday-by-the-sea guesthouses. But they felt it when habits changed.

“A lot were then bought by people who'd never run that sort of business in their lives.

“The problem with it was that people did not reinvest. They didn't modernise. So gradually between the 1960s to early 1980s they were run down to the point no-one wanted to stay.”

And that shift ushered in a different - more unwelcome - type of visitor.

Adds Sir Roger: “It was the back end of the day trips - the beano parties - coachloads of people would come down over the weekend with loads of crates of beer on the coach, tanked up by the time they got to Margate and then piling into the pubs along the seafront.

“Then, at closing time in the afternoon [pubs used to shut at 3pm before reopening in the evening], they'd all be turned out and start fights. That was part of the fun for them but it frightened off the family holidaymakers who didn't like it, for very good reason, so it was a downward spiral.

“The seaside guesthouses, started by the Roxburgh, transformed themselves into Dole-on-Sea. If you were on the dole, anywhere in Britain or Ireland - they advertised everywhere - they’d say come and stay in glorious Margate in a seaside hotel - we've got a bar, it's warm and comfortable and you don't have to work. You can take your dole money and live here cheaply and have a lovely time.

“Suddenly this was a little goldmine for the surviving guesthouses and hotels. Instead of four or five months of summer season, if you're lucky, this was year-round. Money for old rope. But of course, it drove the whole business down and down.

“No one cared about the surroundings. They just wanted a bed to sleep in.”

Sir Roger was one of those MPs who ushered in changes to the law which meant those drawing the dole and staying in hotels could stay in such accommodation for a maximum of six weeks. It didn’t help.

Adds the Tory MP: “What happened was they'd then move onto Brighton and then come back again. So people were just moving around.

“Because of all this, the restaurants went downhill, the Winter Gardens suffered - the glory days of the big rock concerts and entertainment shows there were mostly over by the mid-1980s. Dreamland declined.

“It was, to some extent, happening elsewhere, but because of Margate's proximity to London it provided a bedrock clientele.”

The whole social fabric of these towns was changing.

The guesthouses which shut up shop morphed into flats or HMOs (houses of multiple occupation) - generally appealing only to those with limited financial clout and landlords with little interest in maintaining the Georgian and Edwardian buildings they’d snapped up cheap.

As the tourism trade morphed from fortnight holiday locations into raucous day trips, so the nation’s economy hit troubled waters.

The once relied-upon work dried up. In the early 1980s, just as the likes of Margate were adjusting its budgets downwards, so inflation rocketed (hitting close to 19% in 1981) and unemployment soared (by 1984, in the UK, the jobless rate stood at 11.9% - by way of a guide, today it is around 3.8%).

It was further encumbered by both legacy decisions and modern changes in the workplace.

Folkestone, as an example, had previously limited other industry to other parts of the town - keen not to tarnish its tourist credentials.

Explains Alan Taylor: “The council didn't want a lot of industry. [Drug giant] Pfizer started in Folkestone - they wanted to expand, the council wouldn't let them, so they moved to Sandwich.”

The perception that Folkestone’s port - a popular option for ferries to the Continent - proved an employment alternative was not borne out in reality.

Adds Mr Taylor: “People think the harbour and the ferries brought a lot of people into Folkestone, but they were only passing through. They might stay one night in the town before catching the ferry the next day, but that was it. The ferries didn’t bring people in for holidays.”

Ironically, it was Saga that became the town’s key employer.

Changes to agricultural practices - the phasing out of some key crops and the mechanisation of bringing in others - also reduced job opportunities in the fields surrounding the towns.

With a lack of jobs, many of the younger workforce moved out in search of a decent living elsewhere.

With little other industry to lure people in and few ventures choosing the towns to invest, it was mostly one-way traffic. Which, in turn, drove down property prices.

By the 1980s and 1990s, the situation wasn’t helped by London boroughs shipping in people on their housing lists.

Adds Sir Roger Gale: “It was absolutely a problem in the 1980s and 1990s.

“As an example, I know, some time ago, that one London council put a family of six asylum seekers into Arlington House in Margate. Paid for them there for six months, then said 'well you've been there for six months so now you're part of Thanet so you're no longer our problem'. So they came off their list and went on ours.”

He is, however, quick to point out that the inward migration over the years has brought plenty of benefits too - with many of those moving in starting businesses and becoming key aides to the local economy. But it put a strain on already cash-strapped local councils.

As the 20th century reached its end, many of our coastal towns were perhaps at their lowest ebb. The crowds had gone. The magnificent buildings which once entertained the tourists were too expensive to maintain, commercially unviable or simply falling to pieces. The economies of scale no longer there to support them.

Aspirations were low - both for the population and the younger generation; education around coastal areas took a hit as a consequence.

Day-trippers kept coming, but in lesser numbers and, with fewer attractions to keep them entertained, spent less as a result.

“I've always been proud of the town,” adds Folkestone’s Alan Taylor, “but seeing it rundown was very disappointing.”

By the time Eurotunnel opened, even Folkestone’s cross-Channel trade saw the brakes applied.

Town centres were taking a battering too as out-of-town shopping centres emerged, along with jumbo supermarkets, that sucked retailers out of the high street along with their customers.

Cliftonville, once the beating heart of up-market tourism in Margate in the 1950s was, by 2015, the fourth most deprived area in the entire country. A remarkable reversal of fortunes.

“Seaside towns do suffer from a set of issues that have their roots in the decline of their core industries,” reported a House of Lords Select Committee on Regenerating Seaside Towns and Communities - which started its investigations in 2017.

“Domestic tourism is the iconic example, but fishing, shipbuilding and port activities have all been in long-term decline.

“What makes these areas distinct is the combination of industrial decline and geography. Their location on the periphery of the country places them on the periphery of the economy, bringing consequential social problems. This combination of challenges warrants dedicated attention and support.”

Of course, not every Kent town entered the 21st century fearing the worst.

Whitstable was, quietly but carefully, gathering pace. It had never fully cashed in on the tourism boom that some of its neighbours had during the 20th century. It had stayed small, still reliant on a declining fishing industry.

It was about to take a very different - and very modern - approach to revival. It got a head-start on its bigger Kent neighbours, and one which others around the county would seek to replicate over the years that followed.

At the heart of its offering was that it was still a sleepy, often forgotten, former fishing town. Its streets still narrow, its harbour still a working one. And, thanks to the high-speed rail and road network, very accessible for those from, you guessed it, London.

Food and drink was suddenly about to take centre stage - both of which would become key elements of revivals elsewhere.

Along, of course, with investment and that most surprising and disarming catalyst for regeneration - art.

Kent’s seaside towns were about to have a revival.