In its current borders the Austrian Republic is a predominantly Alpine state, and for this reason, and for its central position, it was compared to Switzerland which, however, has an area equal to half that of Austria (sq. Km. 41,298). The territory of the Austrian state has an average height of about 1000 meters above sea level (Switzerland 1300 meters above sea level), and is mostly occupied by the Eastern Alps, opening eastwards between the Danube and the Pannonian Plain. Only the eastern part of the Marchfeld, the Vienna Basin and the threshold of the Hungarian Plain are truly flat, while Northern Transdanubian Austria, which belongs to the Bohemian Massif, and a large part of Burgenland, have hilly morphology. The rest is essentially alpine and indeed the 3 / 5 of the entire surface are high mountain places.
The largest part of the compact crystalline mid-folds of the Eastern Alps belongs to Austria (see alps) and precisely the northern side of the Rhaetian Alps and all the Noric Alps, consisting mainly of crystalline schists or gneisses, with some granite expansion. The Ötz, Stubai and Ziller Alps belong to this geological complex, on which the border with Italy runs, the High and Low Tauern, the Carinthian and Stirian Alps, south of the Mur (where there are rich iron deposits) and the Leitha Mountains to the Danube. To the north the great belt of the northern limestone Alps extends, with a prevalence of Triassic dolomites and Jurassic limestones, enclosing Paleozoic nuclei, and the northern side of the Reticone and the Silvretta group, on the Swiss border, part of the Alps belong to Austria d ‘ Allgäu and Lech and the inner side of the Bavarian Prealps almost all the Salzburg Alps and the Austrian Alps. The edge of sandstone and molasse, outside the Alpine limestone belt, appears instead in a narrow subalpine area in the Allgäu Alps, in the Salzburg Prealps and at the extremity of the Viennese Forest. The hilly plateau of Miocene sandstone and marl, located east of the Inn, between this river and the Danube, is the last strip of the Swabian-Bavarian Plateau, which then has its geological and morphological confirmation in the so-called Grazer Hügelland and Burgenland, on the eastern slopes of the Styrian Prealps, both rich in lignite and peat. To the south in the Carnic Alps, along the Italian border, the paleozoic limestones of the Siluric and Carbonic dominate;
In Transdanubian Austria the slopes of Šumava have extensive granite expansions; followed, in the Greiner Wald, by azoic gneisses, supported by the Miocene hilly region of Leisser-Gebirge, between the Thaya, the Morava and the Danube.
The characteristic of the relief of the new Austria is given above all by the long longitudinal furrows, which separate the various Alpine folds from each other, opening like a fan over the Hungarian Plain. These broad longitudinal furrows are essentially three: a more northern and fractional one, consisting of the contiguous valley stretches of the Inn, Salzach, Enns, Mur and Leitha, between the central Alpine massifs and the northern limestone belt; the other southern, shorter but continuous, of the Drava, between the ancient schist nucleus and the Paleozoic soils of the southern limestone Alps. Between the two the one of the high courses of the Mur and the Mürz insinuates itself, within the central crystalline masses. The extreme furrows diverge, towards the eastern plain, by almost 160 km.,
The northern corridor is crossed by sections of different rivers, which, then normally flexing to the chains, flow into the plain through transverse locks. Communication between the successive upper longitudinal trunks of the individual valleys is however ensured by very depressed saddles, aligned in the direction of the alpine folds, widely opened by the glacial action; this has also given rise to well-identified valleys, forming real areas of isolation that constitute well-identified physical and historical units, distinguished by regional names. These include central Tyrol (middle section of the Inn), the Zillertal, the Pinzgau (upper valley of the Salzach), the Salzkammergut (upper basin of the Traun), the Ennstal, the Murtal, and the so-called Vienna basin, between the extreme eastern alpine offshoot. For Austria 2017, please check mathgeneral.com.
The southern furrow of the Drava, more uniform and continuous, has only one large basin, that of Klagenfurt, between the Styrian Alps and the Karavanke and extends in the west to the depressed saddle of Dobbiaco, in Italian territory.
The shortest median valley furrow of the Mur and the Mürz, between the Low Tauern and the Styrian Prealps, opens only in the high basin of the Lungau (source of the Mur) and in the alluvial zone of Judenburg; but it communicates both with the northern corridor and with the basin of Vienna and the hilly region of Graz, so that it is of great importance for the internal communications of Austria.
Vorarlberg stands on its own: it has an eccentric position at the western end of the state, because it belongs to the hydrographic system of the Rhine and rather gravitates towards Switzerland.
The central crystalline chain, after the extensive western massifs of Ötz (Wild-Spitze, m. 3774) and Stubai (Zuckerhütl, m. 3511), limited by the two strong depressions of the Passo di Resia (m. 1510) and the Brenner (m. 1370), which enter Italy, rises in the imposing groups of the High Tauern (Gross Venediger, m. 3660; Gross Glockner, m. 3798) with large expanses of snowfields and glaciers and high passes, all above the 2000 m., So that the longitudinal furrows are clearly separated from each other. But further east, the relief in the Low Tauern and in the Austrian Alps (Hochschwab, m. 2278, Schneeberg, m. 2061) decreases, the passes become more numerous and depressed around 1000 m. (Schober Pass, d. 849, Prebühel, d. 1227, Seeberg, d. 1254, Semmering, d. 980), and the more frequent and easier relations between the intermediate valleys.
The northern limestone Alps have their folds broken into blocks and reliefs articulated by a transversal hydrographic network, which leads to deep saddles, or to narrow locks through which the major intra-alpine rivers pass (Inn, Salzach, Enns), so that they are easy and direct communications are made with the lower Danube plain. These reliefs, however, although they belong to the peripheral situation of the pre-Alpine area, have the appearance of the dolomitic regions with tabular massifs bare (Dachstein, Totes Gebirge) or divided into pinnacles and towers above open grassy basins (Hochschwab, Rax Alpen) or towering imposing to the high plain area.
The southern ranges of the Styrian Prealps and the Karawanken, with gneissic and paleozoic soils, have aligned crests slightly higher than m. 2000, few but depressed passes, with a divergent hydrography towards the eastern submontane area with sandstones and Pliocene clays, molded in a soft hilly landscape (Grazer Hügelland), which dies above the terraced diluvial soils of the high Hungarian plain.
The uniform granite rim of the Šumava (Blöckenstein, 1378 m.) Looms over the Danube in echelons and shelves, while further east, on the slopes of the Greiner Wald, it opens into a wide gneissic plateau, between 900 and 500 m. high, from where numerous watercourses diverge, as well to the north towards the basin of the Elbe (Lužnice), as to the east towards that of the Morava (Thaya), to the south towards the Danube (Kamp), and easy are the communications with the Vienna basin, with Bohemia and with Moravia.
Finally, between the northern Alpine ranges and the Danube, as well as between the Bohemian Massif and the Morava, on the arenaceous and marly tertiary soils there is a landscape of medium and low mountain, with a series of higher isolated hills or morainic hills degrading in diluvial plateaus, terraced by the broad lower courses of the Alpine rivers. (See Table CXI-CXIV).
