Trentino-Alto Adige/Südtirol is an autonomous region in Northern Italy. Formed after the First World War, Trentino-Alto Adige came to existence from the aggregation of two distinct historical regions: Trentino, which is an area of Italian language and culture, and Alto-Adige or, more precisely, the South Tyrol (Südtirol), corresponding to today's province of Bolzano. The latter absorbed much Germanization, which began in the eighth century AD. Since 1948 the two provinces of Trento and Bolzano form the autonomous region of Trentino-Alto Adige and since the 1970s, most legislative and administrative powers have been transferred to the two self-governing provinces that make up the region: Trentino (Province of Trento) and South Tyrol (Province of Bolzano). In the last decade, tourism has become a very important component of the province's economy. Hotel and sport facilities are among the best in Italy; the ski resorts of the Dolomites alone can offer more than 1,000 km of ski slopes and about 500 ski lifts. The famous resorts for summer holidays are Madonna di Campiglio, San Martino di Castrozza, Corvara, Canzei, Alpe di Siusi and many others. In addition, there are numerous climatic stations on Lake Garda. The region borders Austria to the north, Switzerland and Lombardy to the west and Veneto to the south and east. The territory is almost totally mountainous except for the Adige valley, which is of fundamental importance for the population and the local economy. The Adige river (410 km), crosses the entire territory from north to south and is the true artery of the region. The Adige is enriched by numerous watercourses and touches all the main cities. To the east of Trentino-Alto Adige, shared with Veneto are found The majestic Dolomite Mountains, or Dolomites (Marmolada massif 3,342 m / 10,965 ft). The shapes of the relief vary from the dolomite mountains to the granite massifs, up to the limestone formations of the southern pre-alpine belt. The relatively easy crossings through which Austria can be reached are three: the Resia pass, the Brenner pass (1,372 m / 4,505 ft) and the Dobbiaco pass (1,170 m / 3,839 ft). By contrast, internal crossings are even higher and snow-covered for most of the time of the year. Among these, the Stelvio Pass (2,759 m / 9,052 ft) on the border with Lombardy; the Tonale pass (1,883 m / 6,178 ft); and on the border with Veneto, the Pordoi pass (2,239 m / 7,346 ft) and the Rolle pass (1,970 m / 6,463 ft). The wealth of small mountain lakes of Trentino-Alto Adige (about 600) is another physical characteristic of the region, which boasts an ancient cultural tradition in favor of environmental protection. Thanks to their uniqueness, many of its beautiful lakes have become as well known as the tourist centers that rise on their shores. The mild climate of Lake Garda allows the presence, on its banks, of typically Mediterranean species: very common are the olive, the laurel and the holm oak. Even the alpine fauna is rich with an abundance of chamois and roe deer. There are also small colonies of brown bears in the woods of the high val Rendena, inside the regional park of Adamello-Brenta. The cultivation of the vine, very selected, is destined to the production of highly renowned wines.