Switzerland has a strong and ancestral dairy farming and cheesemaking tradition. The breeding of cattle, sheep and goats for milk is attested in the Neolithic period and, since Antiquity, cheese has been exported from the Alpine regions. The rugged nature of the country makes approximately 80% of the agricultural land unsuitable for cultivation, which is therefore mainly exploited for cattle and sheep farming. This mode of exploitation has forged a large part of the Swiss landscape, in the Alps, the Jura and on the Swiss Plateau. Today, cheese dairies and mountain pastures in Switzerland produce nearly 500 varieties of cheese, not counting fresh cheeses. Most of these, and all the ones very well known internationally, are semi-hard Alpine or Swiss-type cheeses such as Emmental and Gruyère. Dairy products in general are highly appreciated throughout the country, with butter and cream being classic ingredients of Swiss cuisine. Agriculture in Switzerland#History The breeding of cattle, sheep and goats is attested in the Neolithic period by archaeological remains (bones) throughout Switzerland. There is no direct evidence of cheese production at this time, but the old age of many cattle exhumed in coastal stations on Lake Zurich suggests that at least their milk was exploited, and Germanic peoples already made butter at that time. As the words Käse, fromage and formaggio come from the Latin caseus and caseus formaticus ("cheese made in a form"), it is likely that the art of transforming milk using rennet into fatty, salty and long-lasting cheese was known by the Romans, who brought it to the Celts when they crossed the Alps. Already in antiquity, the alpine regions of Rhaetia exported cheese. "Swiss cheese" is first mentioned 2000 years ago by the Roman historian Pliny the Elder. In his writings of the 1st Century AD, he mentions the Caseus Helveticus, a hard Sbrinz-like cheese made by the Helvetii, who were the tribe occupying the territory of modern-day Switzerland.