Even today, snail cultivation has got a very real economic significance. In France alone, 40,000 tonnes of snails are eaten per year. A large part of those are, even today, snails picked in nature and imported from Eastern Europe and Turkey. From an ecological point of view this is intolerable. From the consumer's point of view it also is, because those snails are not retraceable. Nobody knows where exactly they come from, sometimes not even what kind of snails they are.
Farm snail (Helix pomatia) [RN]
French snail cultivation methods usually aim at fattening the snails by
keeping large numbers of them in small spaces, greenhouses and pens, and feeding
them with artificial food mixes.
In France, usually the Escargot Petit Gris (Cornu aspersum) is cultivated. Though this species cannot compete with the Escargot de Bourgogne (Helix pomatia) in taste and size, it appears to be practically impossible to cultivate Helix pomatia, according to French sources. Only Cornu aspersum, also called the common snail, due to its abundant distribution on the British Isles, has very little demands and so can be kept using the described cultivation methods.
So a solution is sought by cross-breeding with giant Cornu aspersum varieties from North Africa (circumventing any form of nomenclature those are called Helix aspersa maxima), but the result are snails with dark meat that have to be cultivated further, so they more resemble the desired Helix pomatia externally. They are nothing like those in taste all the same.
As so often is the case, the statement, an economically feasible cultivation of Helix pomatia was not possible, is not entirely accurate. Helix pomatia cultivation exceeding simple fattening of snails mainly in Southern Germany has got a old history going back into the Middle Ages. At that time, trade connections. for medieval standards almost worldwide, from peasant Swabia to Vienna and Paris, are witness to the success of Swabian snail trade.
France still remains the main producer of snails. But even the French have to import snails to meet the demands of their market.
Enclosures in a snail farm in Elgg (Switzerland). [RN]
The tale of successful snail marketing has spread also into other countries. Snail raising being a French national discipline, the art of snail cultivation or héliciculture is a young one in Germany, Switzerland and Austria.
In 18th century Austria, though, snail farming had been quite widespread. Several noble's estates even had their own snail farms to provide the lord with a sufficient number of delicacies in shells.
Basically there are several possibilities to keep snails at a larger scale. As described earlier, snail cultivation, like it is usual in France, will aim at fast gains by weight and number of snails at the expense of taste. In contrary to that the German (the revised Italian) method aims at quality rather than merely quantity, keeping snails in an environment close to nature.
This method of snail cultivation close to nature retraces successful historical methods from Southern Germany and additionally introduces modern cultivation methods. Application of herbicides and artificial fertilisers is generally avoided, instead legumes are used for a natural nitrogen fertilisation - green fertilising instead of artificial fertilisers. Finally green food is fed instead of artificial food mixes.
Mangold (spinach beet) - only one of possible food plants. 
The snails are basically kept in pens bordered by fences, in which green food plants are grown before putting in the snails. It is generally not feasible to mount nets against birds and other snail catchers. A metal wall dug deeply into the soil around the farm keeps other snail predators, such as mice, shrews and other four-footed snail hunters, out. Besides, a specially manufactured network fence keeps the snails in. There are, though, many other steps of works to be done, before one snail can be settled into the new enclosure. For example excessive plant growth must be avoided without applying herbicides, that would finally reappear in the snails' organisms.
A special limiting factor is self-inflicted regulation among snails preventing overpopulation. Only 20 at most snails can be kept on one square metre (3300 snails are kept in an enclosure of 150 - 160 square metres). A snail's slime contains a chemical agent limiting fertility. It is visibly disagreeable for a snail to have to crawl over another snail's trace. So the number of snails able to be kept in one enclosure, in the long run, is limited. Which means that from the beginning there must be several enclosures to raise the young snails.
A farm snail in the clover. [RN]
The natural prerequisite for keeping snails in enclosures is an alkaline type of soil with a sufficient content of calcium carbonate. A snail farm can be assumed feasible with certainty where snails occur naturally. Generally, sufficient natural humidity prevailing, it is not necessary to irrigate artificially. Humidity because of dew, but also because of the natural precipitation is usually sufficient. It is because of dew that no net should be mounted against birds: The net would catch the dew and deprive the snails from an important source of water. It is, though, prudent to build perches for birds of prey and to let nature regulate itself.
A sufficient amount of vegetation in the enclosure not only provides food, but also hiding places for the snails. Food plants, such as clover, chicory, turnip rape, spinach beet and wild cabbage can be used. Only fresh green food is not sufficient. In regular periods the snails must also additionally be provided with limp plant food. Legumes naturally provide the soil with nitrates. In empty enclosures the plants are ploughed in to provide a green fertiliser. Additional artificial fertilising so becomes unnecessary.
While a part of the snails is moved into a new enclosure to prevent overpopulation, another part is selected to be processed now. As in any farm keeping animals, there is no way to pass the moment where snails, on which life lots of time have been invested, have to be processed. That means, the snails have first to be collected, and then to be killed.
If snails are processed in a suitable manner, they will not have to suffer unnecessarily. Snails are killed in boiling hot water, which means an instant and almost painless death. The visceral sac with digestive gland and most of the digestive apparatus is removed, which also means that the snails have not to be starved before they are killed.
Usually snails are sold conserved in different ways: In tins in a sauce, or frozen. Transporting live snails is a bit complicated, as the route of transport must remain short, and special transport containers are necessary, otherwise the snails will escape, in which they are specialists.
Lid snails - ready for marketing. 
Mainly two types of snails are marketed: On one hand the crawling snails collected in early summer after laying their eggs, and the fat lid snails, that are collected after the start of hibernation, when they have the largest weight and are richest in content.
Cultivating snails for consummation remains a controversial subject. On one hand to an increasing degree cuisines outside of France begin to show interest in snail recipes. Snail farms also appear quite often in the media: Snails as such and the people who keep them are still considered a little bit queer. So snail farms tend to have a constant amount of audience.
On the other hand there are also voices to be heard, that hold the view, snail cultivation was not vitally necessary and therefore is to be considered a cruelty.
In the end, it will remain with each person on their own to form an opinion and to inform themselves from the different sources.
The Controversial Discussion:
By Symon Bye from Cirencester, England, on May 20th: "Great site! Am currently trying to apply for a licence to breed Roman Snails. As Cirencester was the Roman Capital of England for a time there still exists a Roman Snail population although dwindling. I hope my licence application is successful as I do not want them to die out all together. Thank you for your insights... ". ( Visit the guestbook!)