Foyleside was not the inevitable product of a property boom. It was willed into existence by a coalition of local politicians in the late 1980s, when Derry's economy still bore the marks of two decades of conflict. The Northern Ireland Minister Richard Needham personally lobbied Marks & Spencer to commit, anchoring the development alongside Dunnes Stores. The Derry MP John Hume - who would share the 1998 Nobel Peace Prize for his role in the peace process - publicly championed the project as a generator of jobs and a way to lift the city's image as a regional shopping destination. The original tenants in 1995 included Iceland, Dixons, McDonald's, Adams, and Cafe Kylemore. The 37,160-square-metre site, just over four hundred thousand square feet, made the centre the second largest in Northern Ireland behind Belfast's Victoria Square. For a city the size of Derry, the scale was unusual.

The architectural centrepiece is a glass dome over the central atrium, with a custom Kone glass elevator rising through the open space like a transparent capsule. Until 2016 a water fountain sat directly below the elevator, occasionally drained and converted into a stage for events. Level 3 features a glass-tunnel ceiling, the kind of bright airy detail that screams 1990s mall architecture but has aged better than most. In 2004 a glazed walkway bridge was built to connect the main centre to a new Debenhams anchor store - a four-storey extension on the East Car Park side. When Debenhams collapsed in 2021, Frasers Group bought the building, opened a new Frasers department store on the lower floors, and put Sports Direct on the upper levels along with a GAME store and a Belong gaming arena. On 11 September 2016, in one of the centre's stranger incidents, a man climbed into an unattended Poundland delivery lorry on Newmarket Street, released the handbrake, and rolled it into the side of the centre, damaging the Debenhams glass tunnel before being prosecuted.

To move through Foyleside is to climb the hill at the back of Derry. Level 1, the lowest, holds the Iceland supermarket and Umi Asian restaurant on Foyle Street. Level 2 opens onto Orchard Street and offers a walking route to the older Richmond Centre. Level 3 holds the Food Quarter, added as an extension on top of the West Car Park in 2008, complete with a sometimes-broadcasting local radio studio, a kids' play area, and a sensory room. Level 4 emerges onto Carlisle Road and Bridge Street, the entrance most tour groups use to assemble before walking the city walls a few minutes uphill. In late 2024 a new 8,000 square foot Mango opened on Level 3 in the unit Eason had vacated in 2020; in 2025 the centre announced it was closing the Food Quarter and repurposing the space. Foyleside changed hands again in 2023 when a consortium including the owners of Lurgan's Rushmere Centre bought it for below the £34.25 million guide price.

It is easy to be sniffy about shopping centres. They are not cathedrals. But for Derry - a city whose modern history includes mass emigration, an industrial collapse, and decades of armed conflict - Foyleside was a piece of normality that the city had been denied for years. The Peace Bridge across the Foyle opened in 2011, six minutes' walk from the centre. The 2013 UK City of Culture festival drew nearly a million visitors. Plans to add a nine-screen cinema and 67,000 square feet of office space have been floated and shelved more than once, most recently after the 2023 sale. The mall remains 98 percent let across 55 units. On a busy Saturday it is louder than the cathedral and busier than the city walls combined. Whatever else it is, Foyleside is the most reliable place in Derry to encounter the city's full population at once.