In my copy of A Fashion-Forward Guide to Antwerp, published this year, the highlights of the tourist zone still end at a line somewhere between Grote Markt and the remains of Het Steen, the medieval fortress that once controlled the river Schelde. Beyond this, all the guild houses, Gothic churches and cobblestones peter out. Until recently, everything to the north was 19th century and nasty – a dubious dockland area known as Eilandje, plus the city's red-light district. Nobody went there, not even locals, unless they had to.
However, as I wander up the wonderfully named Vingerlingstraat today, it's clear that a lot of tidying-up has been going on. The ladies and gentlemen of the red-light district now ply their trade in bright glass shopfronts that resemble the cellophane boxes in which Barbie dolls are sold. At the end of Falcolnplein I no longer emerge into a broken landscape of derelict warehouses, but a whole new Antwerp that has at last embraced its maritime past and proved it can be trendy.
There are two big docks up here, one named after King William of the Netherlands and the other, rather surprisingly, after Napoleon. Bonaparte is a great hero in this city because in 1811, he reopened the port, which the Dutch had closed hundreds of years before. Napoleon wanted Antwerp for his invasion of London and called it "a gun pointed at the heart of England". The Grand Invasion never happened, but the emperor bequeathed Antwerp a legacy of two huge, modern working docks. The Willemdok is now a marina – the St-Tropez of Belgium, locals call it – while the Bonapartedok is still being refurbished.
Standing between the two is a building that represents the regeneration of Eilandje. MAS (Museum aan de Stroom) is a new city museum like no other. The building seems deliberately out of context, a 10-storey tower of red Rajasthani slate intercut with walls of rippling glass. At ground level, MAS seems to be made of grey slabs with a few bits of irregular black stone forcing their way through. When MAS opens next Tuesday, visitors will be able to enter (for free, though access to the exhibitions requires the purchase of a ticket) and ascend a sequence of lifts that take them to the very top, from which they can look down on to the piazza they crossed in order to arrive at the front door.
MAS stands for "Museum by the River". It will record Antwerp's long relationship with the outside world via the Schelde, the 350km waterway that rises in northern France. Spread over the 10 floors, there's the chance to see a permanent collection of 470,000 objects, along with temporary exhibits, plus a museum café, a restaurant on the ninth floor, and a roof terrace with panoramic views of Antwerp. Rather than follow a chronological approach, each floor is devoted to a different theme, such as "Display of Power", "Metropolis", "World Port" or "Life and Death".
The director, Carl Depauw, has ensured that the museum is steeped in symbolism. Each duct for electric plugs is covered with a metal cap on which appears an image of Palmanova, the idealised Italian city designed by Vincenzo Scamozzi in the 17th century. "This is to remind us that Antwerp can be the ideal city," he explains. From the 10th floor you stare into the face of a skull surmounting a coat of arms created by local boy Luc Tuymans, the enfant terrible of Belgian art. The image is in fact Tuymans' copy of a memorial plaque to the 16th-century Antwerp painter Quentin Matsys, a dramatic reference to the city's artistic past. The opening exhibition, Masterpieces in the MAS, will also merge past and present. A collection spanning five centuries in Antwerp will be on display until December 2012, contrasting contemporary visual imagery with works by the old masters that date back to the 15th century.
The presence of MAS has led a number of major players to relocate to Eilandje. Immediately opposite, on the Godefriduskaai, is the studio of Antwerp's best-known son: Dries van Noten, the designer who has dressed Michelle Obama and Cate Blanchett. A local television channel has taken up residence opposite the Bonapartedok and the city's dance company, Koninklijk Ballet van Vlaanderen, has its headquarters nearby.
My favourite building, though, is the old St Felix warehouse, which now houses the city archives and a busy, steamy brasserie. This complex was designed in the early 19th century by Felix Pauwels after Napoleon opened up Antwerp to sea trade again. When that trade moved into deeper waters further down the Schelde, the St Felix building was neglected. With all its cranes, platforms and loading equipment still intact, it still resembles a film set from The Onedin Line.
Work on Eilandje is continuing. To the north of the twin docks, past a number of recent boutique restaurants, Europe's only museum of emigration is being created out of the only Red Star Line processing station left in Europe. It was from a brick shed on which the words "Red Star Magazun No 2" is emblazoned that thousands of Eastern European emigrants travelled to Ellis Island. Red Star had similar stations all over Europe but only in Eilandje – thanks to Antwerp's total neglect of its docklands – did one such building survive. Now, with a mixture of Belgian and American money, the processing station is being rebuilt to open next year.
When Eilandje is completed, the final touch will be a new 5km boulevard, which is being built from here alongside the river Schelde. This road will link the docks with the fashionable Parisian-style 19th-century residential development south of the city's medieval core. Ironically the excellent idea to bypass the historic centre was originally proposed by a certain French emperor. After the events of 1815, it was shelved – until now.