“When you tell people in Paris you live near the Gare du Nord, they usually grimace,” sighed Sarah, a French academic in her 50s who has lived on a narrow, traffic-choked street next to Europe’s busiest station for 30 years.

“Architecturally, the station building is superb. But neighbourhoods around stations are never easy, wherever they are in the world.”

Sarah is part of a local residents’ group that has found itself drawn into one of Paris’s biggest development battles in years. The state rail firm SNCF has joined with private developers and is poised to transform the Gare du Nord into a gargantuan €600m (£540m) shopping and office complex along the lines of an airport. The French government says the massive glass refit – which will chop up the station into walkways and mezzanine levels via 105 escalators – is the only way to cope with the staggering 900,000 passengers per day who will be using the rail hub by 2030.

But top French architects and urban planners, including the award-winning Jean Nouvel, are leading a rebellion. In an open letter they slammed the plans as “unacceptable”, “indecent” and a “serious urban mistake”. Paris city hall, which is merely an observer of the project run by the state, has this month vociferously opposed the private commercial plans to add vast shopping space, pleading for it to scaled back. A planning commission verdict on Thursday will determine whether the plans can go ahead. Meanwhile, Paris is grappling with what the essence of station is and how residents should live around it.

Facebook Twitter Pinterest State rail firm SNCF has joined with private developers to transform the Gare du Nord into a shopping and office complex along the lines of an airport. Illustration: Valode & Pistre

“They can argue all they like about what is going to be put inside the station, but if the area around the station isn’t taken into account and altered, with the thundering road traffic eased, the neighbourhood will never improve,” Sarah said.

The Gare du Nord is one of the busiest rail hubs in the world, behind only the biggest Japanese stations. When travellers get off the Eurostar from London or the Thalys from Brussels and Amsterdam they are – unusually for an international terminal – stepping right into a frenzy of local, commuter and northern transport which sees the departure of 2,100 trains a day, with 500,000 daily travellers from the Paris banlieue (suburbs) alone.

And yet the Gare du Nord occupies a comparatively small site wedged into one of the most built-up and densely populated areas of one of the most tightly-packed capitals in Europe. It sits in what was historically a working-class area with a large hospital right beside it, roads hemming it in and almost no green space in the surrounding streets. With trains already running for four storeys below ground, and traffic choking the chaotic and unusually small forecourt, there is precious little room to expand.

For a decade, the 19th-century building, seen as an architectural and engineering masterpiece, has suffered from unflattering comparisons with the calm and gleaming St Pancras in London where Eurostar passengers alight in the UK. Andy Street, the former head of John Lewis who is mayor of the West Midlands, even had to apologise to France in 2014 after calling the Gare du Nord “the squalor pit of Europe” compared with what he called the “modern, forward-looking” St Pancras. But the Gare du Nord’s 700,000 passengers per day dwarfs the footfall of the airier London Eurostar terminal. St Pancras has discreetly tucked its shops beneath lower level arches, while the Gare du Nord has obstructed its main concourse with retail units plonked here and there – at the expense of seating for waiting travellers, who as a consequence are often reduced to sitting on the floor.

Facebook Twitter Pinterest The station is hemmed in by traffic-choked roads. Photograph: Kathy deWitt/Alamy

The French state railway SNCF wants a gleaming new station for the 2024 Paris Olympics, even though many architects believe this deadline is too tight. But the giant scale of the project has led to soul-searching about the city’s future.

Paris politicians on the left say private money has been allowed to dictate the project and threatens the very fabric of the station. France’s indebted state railway company now renovates Paris stations in partnership with commercial property giants, who stump up the cash and claw back profits by putting in large numbers of shops. The €600m plans for the Gare du Nord – drawn up with the supermarket giant Auchan – would turn the Gare du Nord into a gargantuan shopping and office complex along the lines of an airport. There will be separate spaces for arrivals and departures, which will push travellers up and down a striking number of walkways and escalators to get to and from the tracks while passing the maximum amount of shopping opportunity. Like an airport, there has even been discussion of putting up signs warning people how long it will take to reach their platform.

Paris city hall – which is not in charge of the project – has for a year pushed for changes from the sidelines, saying there wasn’t enough space for bikes, not enough thought about rail-users and too much commercial focus, that the project was ridiculously big just to enable a private firm to make money. But suddenly this month, Paris city hall under Socialist mayor Anne Hidalgo, toughened its stance, arguing the “needless” shopping complex should be scrapped and instead the state should fund a much smaller and simple refit. The government and the state railway insists the full project must go ahead if France’s image is to be upheld for the Olympics.

Facebook Twitter Pinterest The busy main concourse at the Gare du Nord. Photograph: Yoan Valat/EPA

Politicians on the left have warned that the French business model of building vast flagship shopping centres is in decline. Several giant shopping complexes are currently struggling, including one in Aubervilliers on the northern edge of Paris and another near Charles de Gaulle airport. Plans to build a giant shopping and leisure complex north east of Paris called EuropaCity have sparked a huge political row, with business unions warning it will kill small shops in nearby towns. Just one stop away by the RER train from the Gare du Nord, the Forum des Halles at Châtelet is already home to a gargantuan shopping centre which was recently recently rebranded as a Westfield. Restaurants and bars dominate the streets around the Gare du Nord, doing a good trade, and many fear that the new station plans will hurt the neighbourhood economy.

The row is so fraught because the Gare du Nord has always had a symbolic place in the social make-up of Paris and the region that surrounds it. It is the gateway to the banlieue and the packed local trains bring professionals to Paris as well as a large proportion of the city’s low-income workers doing crucial service jobs.

Facebook Twitter Pinterest The Gare du Nord has suffered from unflattering comparisons with London’s St Pancras station since the latter’s renovation a decade ago. Photograph: Alamy

“I just want to get straight to work and straight home at night and have a seat on the train,” said Maria 52, who lives on an estate north east of Paris and takes crowded trains to several different cleaning jobs each week.

In 2001, during the last major renovations, a much-praised glass shed brought some light down into the dingy levels below ground. The architect, Jean-Marie Duthilleul, said: “Instead of looking at their feet, now people can raise their eyes.” But the station is still under pressure to rid itself of the sense it is some kind of border between the rich bustle of Paris and a young population discriminated against and pushed to the outskirts. In 2007, hundreds of youths fought running battles with riot police throwing tear gas inside the station after a man was stopped for fare evasion. The station now has the biggest police presence of any transport hub in France.

Alexandra Cordebard, the Socialist mayor of the 10th arrondissement, which is home to the Gare du Nord, lives in an apartment between the Gare du Nord and the nearby, smaller, Gare de L’Est. “Historically, this was the heart of working class Paris, with factory workers and tradespeople with the only remaining large working factory in Paris, the Clairefontaine paper factory,” she said.

The area around the station is the hottest part of the city - we have to limit motorised vehicles and find ways to plant trees Alexandra Cordebard, mayor, 10th arrondissement

She said the compact 10th arrondissement, with 100,000 people living in less than three square km of densely packed streets with no public parks, sees its population swell to 1 million people each day as passengers arrive at the two main stations. The patchwork of local apartments and small studios has a broad cultural mix, including students and artists as well as richer residents who have made money on larger properties.

Three years ago, France’s first supervised injection facility for drug users opened on a street adjoining the Gare du Nord to allow addicts to inject with clean syringes and under supervision in order to curb overdose deaths and transmission of diseases spread by needle-sharing. Cordebard stressed its opening hours are soon to be extended. The station area has also become a focal point for homelessness.

Facebook Twitter Pinterest The streets around the Gare du Nord are densely packed, with no public parks. Photograph: Kevin Clogstoun/Getty Images/Lonely Planet Images

Residents groups insist there must be a post office in the new station as many local services near the station, including the old post office, have closed. Massive traffic jams in front of the station, with motorbikes parked up across pavements, mean it is often a challenge to even cross the road.

Cordebard’s key concern is how the area will remain liveable with the climate crisis and rising temperatures. The station and the nearby hospital emit heat amid vast road traffic pollution, and virtually no green space to counter it.

“If you look at the thermal map of Paris, the area around the Gare du Nord is the hottest part of the whole city,” she said. “It’s one of the hardest parts of Paris to cool down – we have to limit motorised vehicles and we have to find ways to plant trees.”

She added: “For the Gare du Nord to suddenly have this huge extra shopping centre built on top, bringing dozens and dozens of extra lorries a day, bringing extra rubbish each day in a place which can already barely absorb its own daily traffic and activity, I think that’s a problem. It adds to the carbon count, energy consumption and rubbish when we’re already saturated here. Shouldn’t public powers contribute more and build something smaller and better?”

This project will spend colossal sums but not improve travellers’ journeys and their experience of the station Michel Babut, FNAUT

In his office at city hall, Paris’s head of urban planning, Jean-Louis Missika said: “A station is about creating a sense of airiness and emptiness, allowing passengers to calmly connect to this monumental public space, it is not about stuffing it full of obstacles for them.” He wanted a return to “the feeling that stations were the big industrial cathedrals of the 19th century” – with the addition, above all, of more space for bikes and connections to public transport.

At the Eurostar terminal, Florent, 24, a politics student on his way to visit his sister in London, looked out over bustle. “There’s too much privatisation of public space everywhere else already, stations should be for the passengers,” he said. “But I prefer St Pancras, it seems to have more of a link to history.”

And yet the Gare du Nord is dripping in history. The 1864 building, with its striking facade by the German-born architect Jacques-Ignace Hittorff, was built to expand on a smaller earlier station, and was described in the 1920s by the influential architectural historian Henry-Russell Hitchcock one of the great masterpieces of 19th century architecture.

It was built at a time when Napoleon III and his urban planner Georges-Eugène Haussmann were driving grand boulevards through the city’s slums and creating vast prestige projects. Hittorff, who would also be involved with planning the Champs Elysées and placing the Egyptian obelisk in Place de La Concorde, was praised for the technical skill of the Gare du Nord’s vast train-shed roof. His project was so ambitious that its giant metal pillars exceeded French capacity and had to be ordered in from Glasgow. The statues of women representing major and international city destinations on the station’s façade were created by leading artists of the time.

Facebook Twitter Pinterest The €600m plans for the Gare du Nord were drawn up in partnership with the supermarket giant Auchan. Illustration: Valode & Pistre

“Hittorff is extremely interesting for his level of culture,” said the Paris-based architectural historian Karen Bowie, who signed the recent open letter against the latest renovation plans. “As well as an architect, he was an important archeologist, held to have made the discovery that ancient Greek temples were painted in colour. So there is very careful thought to how he used Greek-inspired ornamentation in the station.”

Recent work by scholars in Cologne suggested Hittorff had planned to make more use of colour in the Gare du Nord, Bowie said, in order to “use reflected light to enhance travellers’ experience of the space”.

I don’t think it needs more shops. People are so rushed these days, they just want peace and quiet Patricia, passenger

She said it would be “a shame” to put up a series of heavy new walkways that would cut through Hittorff’s vast station space and mask the ornate back elevation. She was concerned that, unlike the current mezzanine for Eurostar passengers – designed to be temporary – the new additions could be hard to reverse.

Jean-Baptiste Djebbari, the junior transport minister in Emmanuel Macron’s centrist government, insisted that the project was “necessary for the hundreds of thousands of locals and tourists who use the station daily.” He warned that Socialists at city hall were playing politics in the run-up to local elections next March.

Claude Solard, of the SNCF railway company, wrote an open letter to detractors in Le Monde saying that the project would see the forecourt pedestrianised, with vast green planting on the roof, and would aim for a zero-waste policy. He said the funding model of private backers meant ticket prices would not go up.

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Michel Babut of the train-users association FNAUT, said that although there were some positives, such as the Eurostar area of the station being moved to the side and renovated, “this project will spend colossal sums but not improve travellers’ journeys and their experience of the station.”

On the station concourse, Patrica, in her 60s, who used to work in a notary’s office in Etaples on the northern French coast, had been travelling regularly to the Gare du Nord for 40 years. “I love the station building, although it does need more toilets,” she said. “But I don’t think it needs more shops. People are so rushed these days, they just want peace and quiet.”

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