Carso

The Karst Plateau or the Karst region (Italian: Carso; Slovene: Kras), also simply known as the Karst, is a limestone plateau region extending across the border of southwestern Slovenia and northeastern Italy.

It lies between the Vipava Valley, the low hills surrounding the valley, the westernmost part of the Brkini Hills, northern Istria, and the Gulf of Trieste. The western edge of the plateau also marks the traditional ethnic border between Italians and Slovenes. The region gave its name to the karst topography. For this reason, it is also referred to as the Classical Karst.

The plateau rises quite steeply above the neighboring landscape, except for its northeastern side, where the steepness is less pronounced. The plateau gradually descends from the southeast to the southwest. On average it lies 334 m above sea level. Its western edge, known as the Karst Rim (Slovene: ), is a continuation of the Učka mountain range in eastern Istria, and rises to the east and southeast of Trieste, ending in steep cliffs between Aurisina and Duino. Many interesting geological phenomena occur along the Karst Rim, including the picturesque Rosandra Valley (also known as Glinščica).

Because the Karst steeply descends towards the Adriatic Sea, it is less exposed to the beneficial climatological effects of the Mediterranean. In the past, the main vegetation on the plateau was oaks, but these were replaced by pine forests in the 19th and 20th centuries. Forests now cover only one-third of the Karst. Starting the Middle Ages, the plateau suffered radical deforestation for economic reasons. Although much of the wood for the closely spaced piles that support the island city of Venice, Italy came from this region, Venice carefully managed the Karst forests as a reserve for naval timber. The most radical deforestation occurred in the mid-nineteenth century due to clear-cutting by local farmers and conversion of the land into pastures for sheep.

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Wikipedia