mountain range and the flatlands are clear; in other places such as Geneva, the demarcation is less clear. The countries with the greatest alpine territory are Austria (28.7% of the total area), Italy (27.2%), France (21.4%) and Switzerland (13.2%). The highest portion of the range is divided by the glacial trough of the Rhône valley, from Mont Blanc to the Matterhorn and Monte Rosa on the southern side, and the Bernese Alps on the northern. The peaks in the easterly portion of the range, in Austria and Slovenia, are smaller than those in the central and western portions. The variances in nomenclature in the region spanned by the Alps make classification of the mountains and subregions difficult, but a general classification is that of the Eastern Alps and Western Alps with the divide between the two occurring in eastern Switzerland according to geologist Stefan Schmid, near the Splügen Pass. The highest peaks of the Western Alps and Eastern Alps, respectively, are Mont Blanc, at , and Piz Bernina, at . The second-highest major peaks are Monte Rosa, at , and Ortler, at , respectively. A series of lower mountain ranges run parallel to the main chain of the Alps, including the French Prealps in France and the Jura Mountains in Switzerland and France. The secondary chain of the Alps follows the watershed from the Mediterranean Sea to the Wienerwald, passing over many of the highest and most well-known peaks in the Alps. From the Colle di Cadibona to Col de Tende it runs westwards, before turning to the northwest and then, near the Colle della Maddalena, to the north. Upon reaching the Swiss border, the line of the main chain heads approximately east-northeast, a heading it follows until its end near Vienna. The northeast end of the Alpine arc, directly on the Danube, which flows into the Black Sea, is the Leopoldsberg near Vienna. In contrast, the southeastern part of the Alps ends on the Adriatic Sea in the area around Trieste towards Duino and Barcola. Passes The Alps have been crossed for war and commerce, and by pilgrims, students and tourists. Crossing routes by road, train, or foot are known as passes, and usually consist of depressions in the mountains in which a valley leads from the plains and hilly pre-mountainous zones. In the medieval period hospices were established by religious orders at the summits of many of the