Alto Adige, the alpine and most northerly part of Italy which shares with its neighbour trentino a preponderance of international varieties and the absence of a detailed doc system. With the Austrian Tyrol to the immediate north, its culture is firmly Germanic and its first language is German. Officially known as Südtirol—Alto Adige, and part of Austria until it was annexed by Italy after the First World War, the region owes the Italian part of its name to the River Adige (Etsch), flowing south-east to the Adriatic. At the capital Bolzano the Adige is joined by the Isarco (Eisach) River from the north east, forming a y-shaped valley on whose slopes viticulture has been practised for millennia. Vineyards are planted from 300 m up to 1,000 m (3,280 ft), while the valley floor is reserved for other fruits, plus the occasional large-scale vineyard which can be worked mechanically and is therefore more lucrative than apple orchards.