Soumaya Museum: Move over, Mr Getty

Carlos Slim, the world's richest man, today opens the Soumaya Museum in Mexico City, which will house his mind-blowing collection of art. Juan Carretero visits.

It was no small party in Mexico City the other evening. What else would you expect when the host is Carlos Slim Helu, the richest man in the world by a wider margin than ever according to the latest Forbes billionaires list – that would be $74bn in his account – and the occasion is the inauguration of a new museum to display his personal art collection. No wonder guests included the likes of Mexican President Felipe Calderon, Nobel laureate Gabriel Garcia Marquez and British financier Sir Evelyn de Rothschild.

Set in the heart of the fizzing Polanco district, the Soumaya Museum opens to the public today. You may need a few moments to absorb the drama of the building itself before even considering walking inside. When you do, it will quickly become apparent that there's not much humble about the art either.

In fact, it would take four more museums of the same size to house the entire collection of Mr Slim's conglomerate, Grupo Carso. It includes 70,000 pieces that span almost 10 centuries. Among the work likely to be on display at the outset is Rodin's The Thinker – Slim has the largest Rodin collection outside of France – as well as works by European masters such as Leonardo da Vinci (notably Madonna of the Yarnwinder), Titian, Tintoretto, El Greco, Rubens, Van Dyck, Dali and Murillo.

It is a collection so broad – add to the pot pieces by Modigliani, Chagall, Ernst and Miro, as well as the great Mexican muralists Siqueiros and Rivera – that making it all into a digestible whole will be the main challenge of the museum's curators. Furniture and archeological treasures, including coins and spoons, are also part of the catalogue. Clearly, there will not be space for everything all at once and some of the collection will be rotated through the Soumaya.

At 71 years old, Slim is looking for the Soumaya, as his gift to Mexico, to shape his final legacy. As President Calderon noted, its opening will see the "old masters of Mexico" displayed for the first time alongside the European masters. Not that it won't have competition in Mexico City, home already to such institutions as the National Museum of Anthropology and the annual Zona Maco Mexican Contemporary Art Fair. Art galleries here are abuzz with collectors searching for the next Gabriel Orozco, the young Mexican artist whose solo exhibition just ended at the MoMA in New York and is now at the Tate in London.

Also coming soon is the private Jumex Collection, which, after years of amassing work from contemporary emerging and established artists, is building its own exhibition space, designed by the British architect David Chipperfield, just across from the new Soumaya. The two museums will be connected by a new park.

Slim's museum is named after his late wife, Soumaya, with whom he had six children and who died from kidney disease in 1999. It was she who first encouraged his appetite for art. An engineer by training, he comes from an immigrant Lebanese family of retailers. He built his empire resuscitating undervalued companies. Today he delegates his day-to-day activities to members of his immediate family, and his conglomerate has tentacles extending into telecommunications, retail, banking, infrastructure, real estate and drilling. In Mexico, they say, everyone pays something into the Grupo Carso every hour of every day. Its core money-maker is America Movil, the Latin American cellphone giant.

Some might see in the Soumaya a gesture of contrition from a man often accused of monopolistic abuses – his cellphone rates are among the highest in the world – and of lagging behind the philanthropic pace of fellow billionaires like Bill Gates and Warren Buffet (numbers two and three on the Forbes list) Possibly so. It's true that the museum will be free to the public and open seven days a week. But it is also just one part of a $490m new real-estate development called Plaza Carso, which is already dotted with Slim properties including shops, a five-star hotel, offices and high-end condominium towers, all in well-heeled Polanco on the site of what used to be a tyre factory.

Now in place of post-industrial blight stands an edifice that at first is so bewildering it appears to reflect some sort of virtual reality. With an immensity of scale and absence of discrete facades it might almost be a coiled primeval creature straining to burst from the skin of a reptile. If there is a sculptural quality to the structure that is no mistake: it alluded to the energy and the contours of the works of Rodin inside. Yet it has unmistakable sex appeal as well, thanks to myriad colours and curves as well as 16,000 mirrored steel hexagons, made by hand. Inside, meanwhile, the spiralling sweeping ramps reaching seven stories high recall Frank Lloyd Wright's Guggenheim Museum in New York.

On a recent Friday afternoon, the building's architect, Fernando Romero, is drinking tea in a downtown café with two of his colleagues, while fanning through a thick set of drawings that look more like a CAT-scan of an alien than a building with walls and windows. They are hurriedly working out the last details before the museum's debut. The pressure is on and it later becomes clear, when he walks me through the site, that it is still not quite ready for prime time. Lighting needs to be adjusted and some rough edges need to smoothed. Yet for a project of this calibre to be constructed within 12 months is still remarkable.

Romero explains that the idea was to build something very contemporary but with a strong connection to the collection it would house. To achieve a structure that would support the sweeping double curvatures of its exterior walls, he exploited the hexagon, a geometric shape with all the structural and visual parameters he was looking for. "The façade is very contemporary but also very baroque and ornamental, it's like a medieval dress," he suggests. "The outcome came about by translating the specific needs of the collection into the structure, whose skeleton consists of 28 tubular-steel columns of different curvature and thickness interconnected by rings."

Romero is married to a Slim daughter and he worked closely with his father-in-law to stay within budget – every billionaire's fetish – while using local expertise and materials. While in his mid-20s, Romero worked for Rem Koolhaas in Holland and is proud to be part of a generation of architects that went on to design and build some of the most exciting contemporary buildings around the world. He speaks of his interest in "the potential power of architecture as a catalyst for social change". Born in 1971, he is already Latin America's most celebrated young architect.

There is a narrow entrance, after which the main atrium opens up and impresses merely by dint of its scale, the sensuality of the lines and the purity of its soft snow-white walls which hug The Thinker without taking away from the energy of its pondering posture. It brings Le Corbusier's chapel in Ronchamp to mind, a building that was itself arguably a forerunner to the famous public edifices of the American architect Frank Gehry. Romero has given us eroticism which, through winding, infinite lines, verges on the mystical. If classical architecture gives you a sense of order and balance, here the feel is ethereal and otherworldly.

Some might call it an exercise in self-aggrandisement. But by building the Soumaya, Slim has given to his own home town more than the sum of his collection of art pieces. He has given it a whole new cultural institution – and a thrilling new treasure of modern architecture – that will hold its own around the world.