It's gone from rundown and unloved to the great hope that could put the town on the map internationally.
Run by a trust on behalf of site owners Calderdale Council, its re-opening after an extensive restoration in the summer of 2017 was a timely tonic for Halifax and a district which has suffered its fair share of economic and social woes since the recession.
Around 5,000 people were expected to visit on the first day to explore the new independent shops, bars, restaurants and exhibitions - but over 23,000 turned up. Every cashpoint in the town centre was emptied of money, restaurants ran out of food and the print run of welcome leaflets proved woefully inadequate.
A relic of a more prosperous past
The Piece Hall Trust's chief executive Nicky Chance-Thompson married a Halifax native and her first glimpse of the town's neglected Georgian gem was in 2006, when it was a shadow of its former self. Once a regional centre of cloth trading, it later became a wholesale market and a Victorian public square before the old merchants' units were converted into shops. The markets left in the mid-1990s.
"It was sad, rundown, with few shops. It was not a place that people would really visit. It was the first building in Halifax my husband took me to see, but it was in decline - a relic."
Nevertheless, Nicky could see its potential to revive.
"It reminded me of St Mark's Square in Venice and Covent Garden in London - but without the vibrancy."
Heritage Lottery Fund cash allowed the council to realise their vision of bringing The Piece Hall back to life as Halifax's cultural centrepiece and a catalyst of regeneration, and a trust was formed and awarded a 125-year lease with peppercorn rental terms.
"One of the first things we did was to get rid of the cobbles - the old courtyard was dark and covered in soot, and they weren't original Georgian cobbles anyway. It caused a bit of an uproar - it's become a local joke that you don't mention the cobbles! But after we levelled it out, it looked like a lovely European square - it was stunning.
"We wanted to fill the place with shops, bars and restaurants, put on events and become the key economic driver for Halifax."
Roger Marsh OBE later joined the trust as its chair, and his vision echoes Nicky's enthusiasm.
"We are here to make sure that this historic building is purposed for today and tomorrow. We need to retain its past while also taking it forward. In 10 years' time, we want Lonely Planet's guide to England to be telling people to visit The Piece Hall - it could become our Pyramids or Taj Mahal, there's nothing else like it in the world. Our ambitions are grand but simplistic.
"Previous attempts to regenerate it have run into sand, but we want to create an international icon that is sustainable and resilient."
The Piece Hall has numerous colonnades but just three main pillars - culture, trade and heritage.
Retail, food and drink tenants were carefully selected to ensure their aims complemented the overall ethos, and the result is a mutually supportive and creative community of traders that Nicky refers to as an 'ecosystem'.
"We had to decide what to change. We built a modern extension to give us space for restaurants and a function room - we run a restaurant, deli and an ice cream parlour, which provide us with a revenue stream. We managed to expand without interfering with the building.
"The Piece Hall hadn't been marketed for a decade - we were starting from Ground Zero. It didn't exist like this before."
It's clear that both Roger are Nicky are stunned by the scale of The Piece Hall's unprecedented success.
When Antiques Roadshow filmed in the courtyard - the first time they'd visited a building that wasn't a stately home - 20,000 people turned up, a record for the programme.
Elbow have played a gig and Kaiser Chiefs have also sold out an upcoming show - yet Roger dreams of one day attracting Bon Jovi and Sir Paul McCartney to Halifax. Tim Burgess even approached the trust to ask about playing the venue with The Charlatans.
"We appeal to so many audiences. With our street food festivals, like Chow Down, we appeal to the Leeds and Manchester crowd, and with the Gentleman Jack connection we have fans of the series coming," says Nicky.
The astonishing statistics keep flowing - last year The Piece Hall received more visitors than the Tower of London and was the second most Googled attraction in Yorkshire, beaten only by York Minster.
Marks and Spencer chose to retain their Halifax store due to The Piece Hall effect, and it has prospered since. Historic England called it 'the most successful renewal project of its time'.
A beacon for a new Halifax
There was initial cynicism from Halifax residents, who scoffed at The Guardian's now-notorious article declaiming that the town was the 'Shoreditch of the north'.
Nicky prefers to think of the east London hipster enclave as the 'Halifax of the south'.
"People are very proud of The Piece Hall and they deserved better - it needed to shine. It's now a question of how big we can go. They have taken their Piece Hall back.
"There was a sense of excitement when we re-opened, and renewed hope that things were on the up. It's a revolution here, not evolution."
The retail units are full and rarely come up for let, thanks to the stringent vetting process.
"It is becoming the Covent Garden of the north. We have award-winning stores - the bookshop, the record shop. It's experiential shopping and there are things here that you can't find anywhere else. Elder is in the Good Food Guide now (Halifax's first entry)," says Roger.
"We made some difficult decisions, and it was hard to find the right people. We asked them to open seven days a week and work long hours and to be sustainable during tough retail times. But they have responded to us and have created the environment we wanted - they keep The Piece Hall interesting. People come here for events but come back because of the shops," adds Nicky.
Piece Hall trader Jim Bottomley, who opened an eyewear boutique as an expansion of his 71-year-old family optician's business, agrees that he had to 'jump through hoops' before being awarded a tenancy.
"We knew this would be a net to catch clients with. Our shop in the town centre is a bit fuddy-duddy, so we were looking to open a small, high-end showroom and concentrate on that market. We could do that at The Piece Hall and it has brought a boost. We have stock from Milan, Paris and Munich, some of it is a bit unusual but it seems to fit in here.
"The current Piece Hall team have been brilliant and so helpful. We've since won a national award, which is a real feather in our cap.
"I try to use the other businesses in The Piece Hall when I can - we send chocolate from The Chocolate Box as thank-you gifts.
"We've had visitors from Canada and New Zealand, all over the world - the footfall has been brilliant. It's become a real attraction, and a different sort of commerce. The town is really benefiting from the influx of people."
Looking to the future
Roger describes The Piece Hall's courtyard as 'a big piece of outside' and it will come to the fore even more over the next few years.
They hope to bring an ice rink for Christmas and eventually launch hot air balloons from the square - in tribute to a 19th-century balloon show that was witnessed by Anne Lister, Gentleman Jack herself.
A popular sculpture trail designed in collaboration with the Yorkshire Sculpture Park returns this winter after attracting 400,000 visitors last year, and the Tour de Yorkshire race is back next May. Future outdoor concerts will include classical, opera and electronic music.
Gentleman Jack tourism is a seam that The Piece Hall Trust is keen to mine. Anne Lister, the businesswoman who lived at Shibden Hall and whose unconventional life was the subject of last summer's BBC period drama, famously derided The Piece Hall during its heyday as a cloth hall, and considered visiting for commercial purposes to be beneath her social station. She did, however, watch public entertainment there - she once arrived too late for a fireworks display - and fans of the series have been flocking to one of the few local buildings from her lifetime that has survived intact.
Two and a half years on, the restoration hasn't been without its challenges - the 250-year-old building was designed for horse and cart deliveries but must now accommodate superfast broadband for the businesses within. Yet ultimately, it has fulfilled the wishes of the nine of out 10 Halifax residents who responded to a survey to say they simply want their Piece Hall to be somewhere to eat, drink, shop and enjoy accessible outdoor events.
"We want to become a big ticket attraction within the context of Yorkshire. Half of Yorkshire still hasn't heard of The Piece Hall," adds Roger.
"Halifax can now stand as tall as the cities around it. We've not got going yet!"