The legendary Citroën Aulnay plant: 40 years of automotive heritage

A few years after deploying the Rennes plant, Citroën faced the physical constraints and logistical limitations of its historic Quai de Javel home in Paris. Becoming increasingly obsolete for modern high-speed production, this Parisian cradle forced Citroën to seek a new horizon to sustain its manufacturing presence in the Île-de-France region. The carmaker set its sights on the commune of Aulnay-sous-Bois in the Seine-Saint-Denis department. Offering massive geographical scale and ideal connectivity with newly emerging transport networks, this site was destined to become the stage for a major industrial adventure. For forty years, the Aulnay-sous-Bois plant would embody the beating heart of Citroën's mass production, tying its destiny forever to millions of motorists across Europe.

The genesis of Aulnay-sous-Bois: securing Citroën’s Paris roots

By the late 1960s, Citroën’s executive leadership faced an undeniable reality: the historic facility at Quai de Javel, nestled in the very center of Paris, was structurally doomed by the evolution of automotive manufacturing. The urban site suffered from critical handicaps, notably a severe lack of space, the technical impossibility of expanding existing structures, increasingly congested access for heavy-duty supply trucks, and prohibitive logistical costs. To secure its future, the double-chevron brand had to design a completely new factory from the ground up, optimized around the most advanced production philosophies of the era.

The long-term strategy involved progressively transferring manufacturing out of Javel to two primary hubs: the existing Rennes-la-Janais facility and a brand-new complex in the Greater Paris area. The final choice landed on Aulnay-sous-Bois, located in Seine-Saint-Denis. This specific location boasted exceptional advantages, starting with a colossal plot extending over nearly 170 hectares. Furthermore, its geographical positioning offered direct access to the A1, A3, and future A104 motorways, while sitting immediately adjacent to Le Bourget airport and the developing hub of Paris-Charles de Gaulle. Construction on this titanic project officially began in 1971, paving the way for the plant's grand inauguration in 1973.

An ultra-modern infrastructure and a historical social melting pot

From day one, the Aulnay-sous-Bois complex established itself as one of Europe's most advanced industrial footprints. In stark contrast to the vertical and cramped layouts of Javel, the entire manufacturing workflow was engineered for high-volume mass production and seamless horizontal component routing. The plant integrated every phase of a vehicle's birth, housing state-of-the-art body-in-white (ferrage), paint, and final assembly workshops, alongside heavy-duty stamping presses. The infrastructure featured an outstanding integrated supply chain network, incorporating its own dedicated railway terminal for vehicle shipping, immense storage compounds, and internal test tracks.

Beyond its technical supremacy, the factory quickly grew into an economic and human titan for the entire region. By the mid-1970s, employment figures peaked at around 6,000 direct employees, supported by several thousand additional jobs throughout local automotive suppliers. The facility attracted a vast workforce driven by immigration waves from Spain, Portugal, North Africa, and Sub-Saharan Africa, turning the plant into a profound social melting pot. This human journey was mirrored by an era of intense labor activism. The labor strikes of the 1980s at Aulnay remain among the most significant in PSA's history, placing the site at the center of national debates regarding factory working conditions and collective bargaining—especially given that Citroën's management had initially attempted to restrict the influence of the CGT union during the highly charged post-May 1968 era.

Forty years of production: From the initial DS to millions of Saxos

The plant’s trajectory experienced a defining shift in 1976. Just three years after the factory opened its doors, Michelin sold Citroën to Peugeot, giving birth to the PSA Group. This corporate restructuring deeply altered the industrial footprint of the site, which opened its assembly lines to a vehicle from the lion brand for the first time: the Peugeot 104, built at Aulnay between 1977 and 1982. Despite this temporary crossover, the factory retained an almost purely Citroën soul throughout its lifecycle, achieving a grand total of 8,568,391 vehicles manufactured across four decades.

The timeline of vehicles produced reflects the modern evolution of the brand:

• Citroën DS (1973-1974): Strategically chosen to calibrate and fine-tune the assembly lines at a controlled pace before high-volume models arrived. It remains the least produced car in the history of the site.

• Citroën CX (1974-1989): The first massive pillar of the plant, with over one million units built here.

• Type H (1975-1981): The iconic commercial van completed its legendary production run on the Aulnay lines.

• LN and LNA (1976-1986): The very first collaborative project born under the early PSA era.

• Citroën Visa (1979-1986): A popular supermini that accompanied the early growth of the factory.

• Citroën AX (1986-1995): A phenomenal commercial success, with more than 1.06 million units rolling out of Aulnay.

• Citroën ZX (1991-1996): The compact hatchback that bridged the gap into the 1990s.

• Citroën Saxo (1995-2003): The all-time production champion of the site, yielding over 1.66 million units.

• First-Generation Citroën C3 (2002-2009) & C2 (2003-2009): The modern supermini duo that successfully took over the mantle from the Saxo.

• Citroën C3 II (2009-2013): The final vehicle to showcase the historic plant's manufacturing expertise.

2014: The twilight of the plant and the end of an era

The dawn of the 2010s signaled the irreversible decline of the Seine-Saint-Denis facility. Confronted by a severe contraction of the European automotive market and heavy financial losses, the PSA Group suffered from significant industrial overcapacity. In July 2012, CEO Philippe Varin officially announced the definitive closure of Aulnay, a painful decision directly affecting roughly 3,000 employees. On October 25, 2013, the very last vehicle—a grey Citroën C3 II—rolled off the assembly line. Manufacturing of the popular hatchback was subsequently transferred to the Poissy plant, and while a residual operation handling replacement parts continued until 2014, the industrial heart of the site had stopped beating. PSA launched a comprehensive redevelopment plan to reassign personnel to other group factories or transition them to new corporate entities setting up operations on the land, such as ID Logistics.

Yet, Citroën's footprint at Aulnay did not vanish instantly following the end of car assembly. Since 2001, the site had been home to the Conservatoire Citroën, an extraordinary heritage center gathering hundreds of historic vehicles, secret engineering prototypes, concept cars, presidential limousines, and iconic motorsport racers. The factory also housed PSA's emissions testing laboratory, responsible for certifying all new group powerplants before that specific operation was relocated to Mulhouse. The final closure of the Conservatoire on this site in 2024 brought a formal end to the very last chapter of the double-chevron brand at Aulnay-sous-Bois, permanently cementing the location as one of the most visible symbols of industrial transformation in the Île-de-France region.

When viewed against the backdrop of century-old automotive history, the operational lifespan of the Aulnay-sous-Bois factory was relatively brief, spanning exactly forty years between its 1973 opening and the cessation of manufacturing in late 2013. Nonetheless, those four decades of production—almost exclusively dedicated to the Citroën universe—endow the site with immense historical weight and unquestionable significance within the brand's legacy. Alongside the legendary Quai de Javel and the Rennes-la-Janais plant (which stands today as the very last major active industrial bastion for the manufacturer), Aulnay left an indelible mark on French industry, leaving behind the memories of a formidable manufacturing hive whose creations continue to travel the world by the millions.