and the lakes) is one of the highest valleys of the Alps and the only Swiss region in the basin of the Black Sea. The Grisons is Switzerland's largest and at the same time easternmost canton. Its geography, essentially marked by the
Alps, is complex and encompasses a wide range of climates and ecosystems. It is one of the three large southern Alpine cantons, along with
Ticino and
Valais, which include regions on the south side of the Alps. But in contrast to those (and all other cantons), it fully extends on both sides of the great Alpine barrier, from the northern plains at
Maienfeld to the southern plains at
Roveredo. However, a large portion of the canton is neither clearly north nor south of the Alps, it is the
Engadin (the "garden of the Inn"), a large inner Alpine valley oriented towards eastern Europe. Therefore there are parts of this canton in four of the
five drainage basins of the country. The north of the canton is drained by the
Rhine (ending in the North Sea), the south by the
Po and
Adige through several affluents (Mediterranean Sea), and the Engadin by the
Danube through the
Inn (Black Sea). The Grisons lies fully within the Alps, with elevations above sea-level ranging from . It is
both one of the highest and lowest cantons of Switzerland, and the second-highest when considering mean elevation. As a consequence, its topography is extremely rugged and many of the highest settlements in the country (and Europe) are found there, notably in the Upper Engadin. The mountains are numerous; well over 1,000 summits are in the canton. The highest is
Piz Bernina, closely followed by numerous peaks in the
homonymous range. Other prominent mountains are
Piz Russein,
Piz Kesch,
Calanda,
Aroser Rothorn and
Rheinwaldhorn (see
list of mountains of Graubünden for a more exhaustive list). The canton includes numerous subranges of the Alps other than the Bernina. These are the
Albula, the
Bregaglia, the
Glarus, the
Gotthard, the
Lepontine, the
Livigno, the
Plessur, the
Oberhalbstein, the
Ortler, the
Rätikon, the
Samnaun, the
Sesvenna and the
Silvretta ranges. (here at the
Rhine Gorge) is one of the largest rivers in the canton. The regions on the north side of the Alps are all drained by the Rhine and form an intricate network of valleys. The Rhine is both one of the longest rivers within the canton and the only one flowing directly into a sea. The
sources of the Rhine are found in the west of the canton and form the
Anterior Rhine and the
Posterior Rhine. These two rivers converge at
Reichenau to form the Rhine in the strict sense of the term. Just after the convergence, the valley opens and its floor constitutes the flattest plains of the canton, from
Domat/Ems to
Fläsch at the St. Gallen border. In the area around
Chur, at the foot of the
Calanda, the Rhine progressively changes its direction, from eastward to northward. The Anterior Rhine and Posterior Rhine include numerous tributaries as well before their own convergence. The former constitutes a long and straight valley, the Surselva, shut off from the lower plains by the
Rhine Gorge. Its biggest tributaries are the rivers
Glogn,
Valser Rhine,
Rabiusa, forming respectively the
Val Lumnezia, the
Vals Valley and the
Safiental. The other one, the Posterior Rhine, notably collects the waters of the
Avers Rhine and the
Albula, which in turn collects the waters of the
Gelgia and the
Landwasser. Similarly to the Anterior Rhine, the upper portion of the Posterior Rhine is also shut off from the plains by the
Viamala Gorge. After the convergence with the Albula, the Posterior Rhine forms a wide valley, the
Domleschg, until it meets its anterior counterpart. After that, the Rhine collects the water of two important rivers: the
Plessur at Chur, forming the valley of the
Schanfigg, and the
Landquart at the
homonymous town, forming the
Prätigau. Unlike other large cantons, the Grisons includes very few cities. The largest (and capital city) is
Chur. It is followed by
Davos,
Landquart,
Domat/Ems and
St. Moritz, which are, however, far less populated. The canton is particularly renowned for its numerous Alpine resort towns, notably two of the aforementioned ones (Davos and St. Moritz), but also
Klosters,
Arosa,
Lenzerheide,
Disentis,
Flims,
Pontresina and
Scuol. The diversity of the climate of the Grisons is high and comparable to
that of Switzerland. In the southernmost and lowest regions, vineyards and olives are grown, while on the highest summits, snow is found year-round. The inner valleys, particularly the Engadin, are significantly drier than the north and south side of the Alps, being sheltered by the high mountains of the range. On the south side of the Alps,
Grono is one of the top warmest places in the country with an average of . The nationwide record temperature of was registered there. The southern valleys are also significantly wetter than the rest of the canton (1,476 mm of rain in Grono, 849 mm in Chur, and 705 mm in Scuol). The coldest places are naturally at high elevations, such as on
Piz Corvatsch. The localities of the Upper Engadin are amongst the coldest inhabited regions in the country, notably
Samedan with an average temperature of . The cantonwide record-low temperature of was registered there. The low-elevation region of Chur, including the Bündner Herrschaft, experiences naturally less harsh temperatures with an average of . File:Maienfeld Falknis 02.JPG|Lowlands: Vineyards of the Bündner Herrschaft, at the foot of the
Falknis File:Stairs with a view.jpg|Montane zone: Val Bregaglia, at the foot of
Piz Badile File:Val Frisal.jpg|Alpine zone: Val Frisal, at the foot of
Piz Durschin File:PizBernina.jpg|Nival zone:
Piz Bernina from
Piz Morteratsch The area of the Grisons is , 19.2% larger than the
canton of Bern, the second largest canton. Only about a third of this is commonly regarded as productive land of which
forests cover about a fifth of the total area. ==History==