France's large collection of hidden art is being moved from museum cellars in Paris to a secret location in the suburbs to protect the works – ranging from the priceless to the obscure – from possible flooding by the river Seine.
One thousand truck journeys over eight weeks will be needed to clear the vaults of the Louvre, the Musée d'Orsay and four smaller museums of about 100,000 paintings, sculptures, costumes and pieces of antique furniture which are never seen by the public.
The operation, which will cost €5.2m (£3.5m), is the largest migration of art in France since 1940 when treasures were stripped from Paris museums and sent to the south to avoid looting by the Nazis.
This time the threat comes from the Seine which, it is feared, could be due for one of the floods which have inundated the capital roughly once a century. No immediate danger is envisaged (though the river is high this winter). But the damage caused by flooding to museums in Prague and Dresden last year has persuaded the government to take pre-emptive action.
The danger is accentuated by the fact that the two largest art museums in Paris – the Louvre and the Musée d'Orsay – stand on the banks of the river. The last time the Seine overwhelmed its banks and flooded the city, in 1910, the ground floor and basement of the Musée d'Orsay – then a railway station – were inundated.
The scale of the operation has drawn attention to the vast unseen stocks of the French museum service, which has often been accused of mindlessly acquiring and hoarding works of art. Officials have admitted that much of the material being packed into lorries has not been entered on a proper inventory.
The works range from a scattering of masterpieces awaiting restoration, including paintings by Picasso and Matisse, to hundreds of works by relatively minor artists which cannot be accommodated in the public parts of the museums.
Some art lovers have suggested that this might be an opportunity to spring clean the national collection and offer some of the works to provincial museums or even art galleries in other countries. The museum service insists, however, that the works, although unseen, are not forgotten. They have to be kept together, it says, to permit access by restorers, art students and by bona fide researchers.
All 100,000 artefacts are being shipped to a single warehouse at an undisclosed location in the northern suburbs of the capital. For two years at least, and longer if the Ministry of Culture decides that the danger of flooding has not yet passed, the anonymous building will house one of the largest single art collections in the world.
Museum officials have mixed feelings about saying goodbye to their treasure.
"We love keeping them, looking at them, maintaining them," said Serge Lemoine, the director of the Musée d'Orsay. But he admitted it was rare for a museum to be able to keep all its reserves on the main site.
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