Constructed in the 1920s on the sandy Dwyryd estuary of north Wales, beneath Snowdonia’s majestic peaks, Portmeirion’s buildings run the stylistic gamut: Jacobean and Gothic, Norwegian and Regency. They are pink and red, green and ochre. Each roofline differs from the next.

Eclectic, eccentric Portmeirion is one of the most recognisable attractions in Wales. The lifelong project of an architect with a passion for beauty, it would have been easy for the village to be frozen in time, a relic its 1930s heyday. Instead, it has continued to change and evolve. If there’s anything constant about Portmeirion – other than its beauty – it is its capacity for reinvention.

I first came to the village as a schoolboy in 1968. At the time, all I knew was it was featured in the bizarre British secret agent television series The Prisoner. I fell in love with Portmeirion that day. Britain was still going through a self-imposed period of post-war ugliness; it seemed to me terribly important that there was a grownup in the country who believed in beauty.

That grownup, a Welshman called Clough Williams-Ellis, was born in 1883. He was a successful but virtually self-taught architect – and he despaired of the 20th Century’s attachment to Functionalism and Brutalism. He wanted to show, as he once wrote, “that buildings properly situated within a landscape could actually enhance the scenery.” In 1925, Williams-Ellis bought a small estate on the edge of Snowdonia and started proving his point, building on pretty, wooded slopes that ran down to the estuary.

There was already a gentleman’s residence on the estate, which he immediately turned into a hotel. Williams-Ellis always intended that his village – which he called Portmeirion, a fanciful name coined from Merionethshire, one of the 13 historic counties of Wales – would be a tourist destination.

There were a few other buildings, too, mainly stables and outbuildings, which Williams-Ellis embellished in a colourful manner that owed more to style than necessity. “Cloughed up” became a fashionable term for his technique. He painted shutters on the facade of one cottage, attached a statue of St Peter to another. His approach was just as irreverent as his style: he would draw his concept, then let his builders work out how to achieve it.

But most of the village was new – in the sense that new uses were found for old, salvaged pieces of architecture. In the years after World War One and World War Two, modernising architects were demolishing a lot of Britain’s architectural heritage. Williams-Ellis acquired these buildings, or their parts, to reuse – so much so that he declared Portmeirion “a home for fallen buildings”. His pseudo-Town Hall, for example, used a carved Jacobean ceiling that the architect purchased from a Flintshire stately home awaiting demolition – and also recycled an upturned pig boiler to create a copper-painted coronet on its spire.

Portmeirion plays impishly with perspective, too. On a visit this spring, when I arrived at the Unicorn, my pink Palladian “cottage,” I was surprised to find that it took far fewer steps than I’d expected to get from the road outside to the front door: the Neoclassical façade tacked onto the building makes it look much larger from far away than it really is.

Williams-Ellis and his writer wife Amabel hoped that their village would inspire painters. But artists never arrived – perhaps, ironically, because Portmeirion was already a work of art. Still, thanks to Amabel’s contacts with the London literati, many celebrities were soon accepting invitations, including the playwright George Bernard Shaw, novelist H G Wells, architect Frank Lloyd Wright and director Noel Coward (who famously wrote his play Blithe Spirit here in 1941, having left London to escape the Luftwaffe bombing). When Edward, Prince of Wales – perhaps the most eligible man of his generation – came to visit in 1943, Williams-Ellis added a private ensuite to one of the hotel rooms and temporarily increased the village’s entrance fee to £1 to keep down daytripper numbers. By World War Two, Portmeirion had become a visual and social phenomenon, so much so that Williams-Ellis bought a hotel in the Shropshire market town of Shrewsbury to act as a halfway house for those motoring up from London.

When my parents and I first came here as day-trippers in the 1960s, a sliding scale of admission charges was indicated on the toll house wall: your payment depended on whether you were a resident, annual pass member or day-tripper. (“Residents” referred to overnight guests at the resort; no one, aside from Williams-Ellis, owned property). Not that the prices were always followed. The cost of a day pass could suddenly go up in the middle of the day if the village got too crowded as Williams-Ellis wanted his residents to feel relaxed and at home. For all of his quirky instincts as an architect, Williams-Ellis had a clear streak of British pragmatism. He needed Portmeirion to pay for itself or he would not be able to fund his vision.

These days, Portmeirion is always busy. And while fine dining is still offered in the hotel’s Art Deco dining room, the village is more egalitarian, the sliding scale of prices abolished.

Walking down from the Unicorn early in the morning, I passed a row of shops with faux Dutch gabling where a cafe was opening for the day visitors. Outside the pseudo-Town Hall, the empty bottles were being taken quietly out from last night’s reception.

It seemed surprising that such a famous anomaly could survive into the 21st Century – never mind become more popular than ever before.

“The village has always muddled along,” William-Ellis’ grandson and Portmeirion’s managing director, the writer Robin Llywelyn, told me over coffee. "Various members of the family have often pursued their own interests. But somehow, this has worked to the long-term benefit of Portmeirion.”

Susan Williams-Ellis, Llywelyn’s mother and Clough’s daughter, founded Portmeirion Pottery, ceramics based on her original designs, in Stoke-on-Trent in 1960; her Botanic Garden tableware range has become a British classic. Llywelyn himself pursued the arts while running Portmeirion, launching a music and arts festival in the village in 2012. He hopes to soon start a literary festival. “Clough always wanted Portmeirion to be a place for things to happen, where events might take place, to be a setting,” Llywelyn said.

In film, at least, it has been for years. Portmeirion’s variety of architecture has allowed it to stand in for many locations: France (Brideshead Revisited), 1960s Italy (The Green Helmet), Brighton (Under Suspicion), Renaissance Italy (Dr Who), even China (Danger Man). But the two television series that really secured Portmeirion's place in the popular British imagination were 1960s sci-fi drama The Prisoner (with the village making an eerily jovial setting for the Kafkaesque story), and the more recent Cold Feet, the romantic comedy series whose final episode in 2003 turned Portmeirion into a popular wedding venue overnight.

“Clough did not like the idea of Portmeirion being in any way a sterile museum of architecture,” Llywelyn said. “He wanted the place to inspire people to be creative in their own right, be that as artists, writers, poets, musicians, even architects – and for the whole place to provide pleasure and make people happy."

The village certainly continues to make me happy and I find it difficult to imagine life without the occasional visit. Quite why it has such an impact is based, I think, in the fact that Williams-Ellis fought for beauty all his life, considering it a “strange necessity”. And it is because his family have held on to this idea of beauty – in whatever form it comes – that Portmeirion continues to reinvent itself and go from strength to strength.

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