Vanishing down a Grockle Duct: There's nothing wrong with cultural tourism. Except that it is destroying the objects of its gaze

I SPENT 10 minutes at the Louvre on Sunday. I had intended spending a couple of hours on the assumption - you will laugh - that it was an art gallery. I left as soon as I realised my mistake.

The Louvre in summer is, of course, an art gallery only in the imaginations of the French tourist industry and the writers of guidebooks. In reality, it is a Grockle Duct.

Grockles - an offensive noun of dubious etymology meaning tourists - forced to visit the Louvre are ducted into a glass pyramid by studiously offensive officials and thence down into a rather fine subterranean space. This being France, the air-conditioning works in reverse so it is hotter inside than out and, again, this being France, the thousands of milling grockles are sadistically kept in stifling ignorance of what they are supposed to do, knowing only that whatever it is requires long queues.

Not, of course, that it matters, since all they are actually required to do is hand over money to be permitted to shuffle down long corridors, many of which contain paintings, and, if they are lucky, to buy fizzy drinks at prices which, if demanded of Michael Douglas, would have caused him to trash the entire joint with a baseball bat.

Some exceptionally erudite grockles will know that the Louvre contains a painting called the Mona Lisa, and they may make their way towards this painting by following the handy little black-and-white images with arrows thoughtfully, but somehow cynically, provided by the Commissars of the Grockle Duct. They will find the painting in a glass- fronted box in front of which will be a corridor-blocking clot of about 100 other grockles, many of whom will, incomprehensibly, be filming it with video cameras.

Let us be generous. Let us assume that 10 per cent of these grockles have some interest in painting. The remaining 90 per cent will be there because they are visiting Paris and the Louvre is one of the things you do if you visit Paris, the others being Notre Dame, the Pompidou Centre and the Eiffel Tower. This is a lot of Grockle Ducts for one city and, sure enough, when the grockles are in town, Paris does not work. Coaches block the boulevards and la circulation goes into a paralytic seizure. Most of them not being Michael Douglas, this does not appear to worry the grockles, who contentedly sit in coaches and, like Russians suspecting a consignment of sausages, join any queue they happen to see.

We have GDs, too - the Tower of London, Westminster Abbey, the Cutty Sark and, soon, Buckingham Palace. In Athens they have the Parthenon, in Rome the Vatican and the Coliseum, in Madrid the Prado, in Venice they have Venice and so on. In fact, Europe is littered with old things that exist solely to tell the grockles they have been there. In front of Notre Dame I saw one Japanese man set up an expensive camera and tripod and then photograph his girlfriend before the facade. Would they debate that facade when they got home, considering it, perhaps, excessively cold, displaying a rigidity of composition at odds with the Gothic style? No, they would say here is Notre Dame, which is in Paris, and here is my girlfriend, who was also in Paris. Famous French cathedral and girlfriend - together at last]

Travel and grockling - all right, if you must, tourism - now form the second biggest industry on the planet after oil. It accounts for one in 10 jobs in the EC, one in 15 in the world. More than 6 per cent of the world economy and almost 7 per cent of all capital investment is devoted to moving people about and putting umbrellas in their drinks. Thanks to the recession, growth has recently slowed, but some of this has been counteracted by the way the Japanese have been driving their own people out of the country in a showy attempt to reduce their embarrassing trade surplus.

And, of course, all the high growth Asian countries are producing new generations of grockles. At the moment, most tourism is still from Europe and America, but the balance is tilting. Soon there will be a net inflow of visitors as workaholic Koreans and Chinese decide they need to recharge their batteries by queuing to take snaps of Beefeaters.

It is, in short, going to get worse. Now the word 'worse' may not be one you have heard in this context, 'better' is the adjective normally applied. This is because there are vociferous pro-tourism lobby groups - in this country this used to mean the Tiggerish William Davis until he resigned from the British Tourist Authority - insisting that tourists are a good thing and they should be encouraged and looked after.

It is difficult to argue with this in poor countries that have little else, or on Caribbean island states that would barely exist but for holidaymakers. It is even difficult to argue with it in countries like Britain, where the collapse of manufacturing has convinced us that all we can do is provide service industries, of which tourism is the second biggest after finance. Nevertheless, the argument must be put because Europe has a problem of capacity that is verging on the acute and that, assuming an eventual end to the recession, will become critical in the next few years.

The Continent has a limited number of objects - perhaps 20 - that must be visited because, in the grockle mind, they identify the place - Paris is Notre Dame, the Louvre and so on. The problem is that, in deferring to the crowds, the object becomes different. The architect I M Pei had to design that immense entrance to the Louvre to cope with the numbers. Graceful as it may be, that is the sole meaning of the building. Pei has changed a royal palace into a stadium or arena. The specific effect of seeing paintings on the walls of a palace is fatally undermined, if not destroyed completely. Equally, the royal tombs in Westminster Abbey can scarcely be said to retain their resonance when surrounded by a slow-moving snake of crushed tourists.

The point is that the guidebook descriptions, the glance and the snap change the object into what the tourist expects and requires. In its more extreme forms this effect actively manufactures its own objects - self- consciously re-created bits of idealised 'heritage'. This postmodern, virtual reality, theme park side of the tourist business is dispiriting, but negligible. But the problem of the real past - that still embodied at Notre Dame or Westminster - is serious. The only solution here is that real history and real art must be rationed.

This may offend against the original democratic idealism of the age of mass tourism. It is fundamental to the beliefs of the tourist lobby that these things, once created for the delectation of an aristocratic minority, must now be utterly available to the democratic majority. Yet, if the objects are only comprehensible through reasonably peaceful contemplation or through the awareness of space, then crowds render them meaningless. The mass experience becomes an experience of nothing but the most meretriciously familiar. The facade of Notre Dame is not an essay in cerebral Gothic, it is a backdrop for the girlfriend.

Rationing, however, is difficult because tourism is not one industry but hundreds. Ice cream sellers and coach drivers, not to mention curators, have a stake in the Mona Lisa or the vaulting of the Henry VII chapel. In such a context the easiest way is to let rationing happen by a kind of scorched heritage policy - allow the crowd and the prices to get so bad that numbers fall. This, however, does not seem to be happening in Paris, where both prices and numbers are already intolerable.

Other schemes include advance booking or, more unfairly, imposing a limit so that places automatically close above a certain number. My own suggestion is that anything that can be moved out of cities should be moved - paintings and sculpture, for example, should be exhibited in remote countryside locations so that seeing them involves a commitment rather than simply being a desultory filler between shopping and lunch.

But this is just tinkering with something that inspires a deeper unease than the mere problem of ducting the grockles. The ideals of freedom of movement and access have become a single ideal of consumption that contradicts older ideals of the value and, indeed, non-consumability of what is now being consumed. You cannot buy the Mona Lisa, but she can certainly be dissipated and used in ways in which her ultimate value cannot be robust enough to survive. Smart commentators will say that the significance of such things changes with their context. But the point of cultural tourism is that it is a pursuit of what does not change. The grockles are not smart postmodernists, they want to see great works of art in the sense intended by Ruskin or Vasari. The irony of their pursuit, however, is that it has become self-defeating. When they get there, they find that, behind the eyes that still follow you, the great work has turned away in dismay from the impossible demand that it feed so many eager lenses.