Zaha Hadid’s proposal for Reggio Calabria. An internal view is shown below

The urban dystopia which formed the background to Matteo Garrone’s film Gomorrah subverted our image of the architecture of the Italian south. In the decaying Neapolitan housing project, Le Vele di Scampia (the Sails of Scampia), the cancerous concrete seemed a metaphor for the corruption and moral morass of the local mafia, the Camorra.

We have become used to images of benevolent decay in Italy’s townscapes – picturesque piazzas, languid loggias and alleys strung with washing like decorative bunting. Garrone’s film, and images from the 2008 garbage crisis, brutally stripped away those clichés. We do not associate Italy’s south with modernity in any good way, particularly not in terms of architecture.

Yet a rash of announcements is heralding a renaissance in avant- garde architecture in the south. Among the most striking is Zaha Hadid’s proposal for a vast waterside development in Reggio Calabria. Known as the Regium, it constitutes the familiar idea of regenerating a post-industrial waterfront through a theatrical architectural invention. Hadid’s proposal folds and swoops out of the landscape, rearing up like a wave, creating a network of new public spaces. It is designed to contain a museum and a large, multi-functional arts space.

As if this wasn’t enough, Hadid is also building a radical ferry terminal in Salerno. As in many ports, the bulky industrial infrastructure allows little connection between the sea and the city. Hadid’s fluid building with a long, sculptural roof attempts to form that connection, with a network of walkways and ramps that take passengers up from the ground entry level to embarkation on the upper floors. A third waterfront building, the Nuragic Museum in Cagliari, presents an even more space-age landscape, in which the structure’s membranes seem to tear like overstretched bubblegum – although this scheme appears to be mired in fundraising problems.

The most ambitious plan in the notoriously infrastructure-poor south is the Naples subway scheme, which aims to turn stations into artworks. With the richest seams of archaeology in the world, any subterranean construction around Naples throws up a unique set of complexities and juxtapositions. The two stations at Stazione Municipio, by Portuguese architects Alvaro Siza and Eduardo Souto de Moura, respond to the remains of antiquity with exhibition areas defined on one side by ancient walls and the bases of Roman towers and houses. Massimiliano Fuksas’s wackier Stazione Duomo encompasses the remains of a Roman temple, archway and arena. French architect Dominique Perrault’s crystalline shelters at Stazione Piazza Garibaldi sit lightly on the ground, as do the wavy roofs of Miralles Tagliabue’s Stazione Centro Direzionale and the complex glass and steel curves of Rogers Stirk Harbour’s Stazione Capodichino Aeroporto.

There is no attempt at stylistic unity. The new metro is conceived as a heterogeneous series of events: stations by the classically inflected Vittorio Lampugnani and Hans Kollhoff are also planned. The most extraordinary, however, are those by Amanda Levete and Anish Kapoor and by Peter Eisenman.

The former consists of a pair of oddly disturbing organic blobs, one in rusted Corten steel, the other in mirror-polished metal, which swallow the escalators at Monte Sant’Angelo station. “It expresses the tension between art and architecture,” Levete says, “between form and function. The entrances look like they’re being pulled back into the earth. There is an aesthetic as well as social deprivation in the south. Naples is rich in history but this area has little of that richness.”

Eisenman’s proposal for a pair of stations at Pompeii, which evolved out of an analysis of the ruined grid of the ancient town, looks set to become the most loaded and intellectually resonant of the schemes.

Finally, under construction back in Salerno is British architect David Chipperfield’s impressive civic design for the Palace of Justice, a mini-cityscape of sober, serious forms that embody a particularly powerful meaning in the south.

Nearly all of these schemes are being undertaken by a foreigner. When I was studying architecture 20 years ago, we looked to Italy for intellectual and aesthetic succour; it was the home of ideas and intelligence. What happened? “Italian architecture was on a pedestal,” says Stefano Boeri, an Italian architect and editor of the influential magazine Abitare. “But it was based around Aldo Rossi and others who were primarily thinkers. They didn’t necessarily translate these thoughts into buildings. The gap between intellectual architecture and practice got bigger. Now it is huge.”

The assembling of international star names on big projects has become almost a cliché of regeneration, but to see this level of ambition is a surprise. But will these schemes get built? “We are in the south here, it can seem more like Kenya,” says Boeri. “A lot of these schemes will start and be interrupted. And they will stay interrupted. The mafia is powerful not just in Sicily but here, and all the way up to Turin. There is a lot of European Union and government money involved in these schemes and a lot of ‘interest’ in that money.”

Indeed. However, in a region notorious for its congestion and lack of public facilities, these schemes are impressive. Modern architecture has done little for the Italian south; perhaps it is beginning to pay back the dues it owes for aberrations such as the Scampia housing project.