Geography of the Alps: Encyclopedia II - Geography of the Alps - Delimitation

Geography of the Alps - Delimitation

The Alps form a large mountain range dominating Central Europe, including parts of France, Italy, Switzerland, Liechtenstein, Austria, Germany, Slovenia and possibly Hungary (if one includes the Günser Gebirge or the Ödenburger Gebirge in the Alps). In some areas, such as the edge of the Po Basin, the edge of the range is unambiguous, but where the Alps border on other mountainous or hilly regions, the border may be harder to place. These neighbouring ranges include the Apennines, the Massif Central, the Jura, the Black Forest, the Böhmerwald, the Carpathians, and the mountains of the Balkan Peninsula.

The boundary between the Apennines and the Alps is usually taken to be the Colle di Cadibona, at 435 m above sea level, above Savona on the Italian coast.

The River Rhône forms a clear boundary between the tectonically-formed Alps from the largely volcanically-formed Massif Central. Working upstream, the River Rhône turns to the east near Lyon, and forms part of the boundary between the Alps and the Jura that ends at Lake Geneva. An area of flat ground reaches from there to Lake Neuchâtel, continuing the border, with the Jura to the north-west and the Alps to the south east. From Lake Neuchâtel to its confluence with the River Rhine, the Aar forms the border.

The Black Forest is separated from the Alps by the River Rhine and Lake Constance, but exact delimitation is difficult in southern Germany, where the land gently slopes up to meet the mountains (known in German as the Schwäbisch-Bayerisches Alpenvorland, the "Swabian-Bavarian pre-Alps").

In Austria, the Danube runs to the north of the Alps, separating it from the majority of the Böhmerwald, although some small areas, such as the Dunkelsteiner Wald south of the Wachau, belong geologically to the Böhmerwald despite being south of the Danube. The Wienerwald near Vienna forms the north-eastern corner of the Alps, and here the Danube passes at its closest to the Alps.

East of Vienna, only the Marchfeld, a 30-km wide flood plain separates the easternmost Alps from the Lesser Carpathians. After Vienna, the Pannonian Basin, a large area of steppe, meets the edge of the Alps, clearly delimiting the eastern limit of the Alps.

The south-easternmost extension of the Alps is to be found in Slovenia, including the Bacher Gebirge, the Kamnik Alps and the Julian Alps (the last being shared with Italy). The town of Idrija may be taken as marking the dividing line between the Alps to the north and the Karst plateau to the south, which then leads on to the mountains of the Balkan Peninsula.

The remainder of the southern edge of the Alps is clearly delimited by the basin of the River Po.

This delimitation of the Alps is, however, largely subjective and open to argument. In particular, some people restrict the use of the term "Alps" to the higher mountains in the centre of the range, relegating the surrounding hills and mountains to the status of "pre-Alps" or foothills. This can sometimes lead to conflicting definitions, such as Mont Ventoux being considered to lie outside the Alps (there are no comparably sized mountains around it, and it is at a considerable distance from the main chain of the Alps).

It is also not possible to define the Alps geologically, since the same orogenous events that created the Alps also created neighbouring ranges such as the Carpathians. See also Geology of the Alps.

Adapted from the Wikipedia article "Delimitation", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki