When Gavin and Stacey announced their intention to get married in Barry, Gavin’s mother Pam hit the roof.

“Barry Island?… I am not traipsing the best side of my family all the way down to Wales to see my son, my only son, get married in some dirty fairground,” she fumed.

The final episode of Gavin and Stacey will air on Christmas Day, 17 years since it first hit our screens.

In that time there is no doubt the sitcom has drawn droves of tourists to the area – but has it changed perceptions of the south Wales seaside town?

“I think [Pam] was being a bit unkind to the town,” said BBC meteorologist and presenter Derek Brockway who grew up in Barry and still lives nearby.

“There are parts of it that some people might find a bit tacky but it’s got its own character.

“Barry is a special place… it is definitely on the up and that’s been helped by Gavin and Stacey.”

Barry Island was once a popular holiday resort with south Wales’ miners, who would head there with their families during miners’ fortnight, typically the last week of July and the first week of August.

Growing up there in the ’70s, Derek recalled seeing a vibrant Barry Island fall into decline when cheap air travel saw the demise of the British seaside holiday and the town’s Butlins closed in 1996.

“You didn’t necessarily want to go there but since Gavin and Stacey it has put the town firmly back on the map again,” he said.

“It’s much more popular and a nicer place to visit and you’ve got lots more shops, restaurants and cafes open, it’s a popular place.”

Could the renewed interest in the seaside town lead to gentrification?

“I don’t think Barry will ever be posh,” he laughed.

“That’s probably a good thing. It’s a very down to Earth town, lots of brilliant people live there, it will never be [affluent Cardiff suburb] Pontcanna by the sea. It will always be Barry Island or Barrybados as I call it.”

Barry Island is in fact a peninsula.

In the 1880s the island was linked to the mainland as the town of Barry expanded following the opening of Barry Docks by the Barry Railway Company.

In the sitcom, Stacey and her mother Gwen live up the hill from the island on Trinity Street in Barry, with Uncle Bryn just across the road.

The house is located in councillor Naomi Marshallsea’s ward Illtyd and she fondly recalled her children shouting Nessa’s catchphrase “What’s occurring” at tourists taking photos outside Stacey’s house.

“Every single time without fail there is joyous laughter,” she said.

She grew up 10 miles away in Cardiff but said she never visited the town.

“It just wasn’t perceived in a positive way but Gavin and Stacey has definitely changed that,” she added.

She credits the show with bringing “a sense of joy to Barry and a positive feeling of warmth”.

“It has put it on the map,” she said.

She thinks Barry’s image has changed for the better since Pam’s outburst over Gavin’s wedding plans.

“I think it’s probably quite an old-fashioned perception,” she said.

She added as well as the fairground and amusement arcades, Barry was now known for its biodiversity, woodlands and country parks.

Marco Zeraschi, who owns Marco’s Cafe on Barry Island, where Stacey works in the sitcom, said it was hard to overstate what the programme had done for the resort.

“We’re the envy of many, many seaside resorts around the country,” he said.

“People know who we are now, we’re world famous Barry Island.”

He said it had also changed perceptions for the better.

“Gavin and Stacey is always positive, witty, funny, happy, it shows Barry at its best,” he said.

“It shows it in such a positive way – they see the beach and the prom, people get curious and curiosity is the best thing for tourism.

“They come here, we get busier and we employ more people.”

Louis Ross who has run Barrybados gift shop since 2013 said he was amazed at the reach of the sitcom and got at least one fan from Australia each week.

He said without the series his business would struggle in the winter and the finale has made the business the busiest winter yet.

“It brings people to Barry, it has definitely put Barry on the map… it’s everywhere,” he said.

Keith Abber, the manager of the amusement arcades that is home to “Nessa’s slots” said despite the last episode airing Christmas 2019, the series continues to draw crowds to the town.

He said it was down to visitors to “make their own minds up” about what they thought of the resort.

“It’s a typical British seaside town isn’t it,” he said.

Natalie Bolan, who has lived in Barry all her life, sells greetings cards and posters inspired by the show from her shop Dimensional Art at the town’s Good Sheds, a collection of street food, bars, independent shops and local businesses.

She said she had watched the town’s fortunes change as the show gained in popularity.

“Barry was a town only busy in the summer, now it brings people from all over all year round,” she said.

“Even if locals don’t like Gavin and Stacey there is a sense of respect for what it has done for the island.”

Ellie Jones, a customer assistant at Marco’s Cafe, has lived in Barry all her life and is a big fan of the sitcom.

She said she enjoyed watching Gavin’s Essex born-and-bred parents Pam and Mick slowly soften towards her home town.

“As the show went on they grew to love Barry, they wanted to come here,” she said.

“They saw it as a place of beauty rather than somewhere dirty.”

Back in series one in 2007, Pam’s reaction to Gavin and Stacey’s plans to get married in Barry was visceral and her dislike for the town laid bare.

She ranted: “Where you going to have the wedding reception? On the log flumes? And what’s on the menu for the wedding breakfast? Hot dogs and candy floss?”

By the time series three aired two years later she was enjoying the thrills of the fairground, squealing with joy on the very log flume and chomping on the very candy floss she had once mocked.

While sunning herself on the beach with Uncle Bryn, Smithy, Nessa and the rest of the Shipman-West crew, she conceded maybe Barry Island wasn’t so bad after all.

“Wow,” she says.

“This is lovely.”

The final episode of Gavin and Stacey will air on BBC iPlayer and BBC One at 21:00 GMT on 25 December.