The largest coastal city Sarandë is located in the southern part of the region, while smaller villages include Borsh, Dhermi, Himara, Qeparo, Piqeras, and Lukovë. The total length of the coastline is approximately . The most characteristic features of the coastline are the Ceraunian Mountains, which extend nearly along the Albanian Riviera roughly in a southeast–northwest direction. The region is particular fertile and known for its citrus fruits and viticulture, that has a long and special tradition in the region. The coastline is abundant in dolomites from the triassic period, the carbonate rocks follows with limestone from the jurassic period and bituminous schists, cretaceous porcelain and phosphate limestone. The northern mountain range is the most mountainous region in the country and its physical geography and shape is distinguished by the convergence of two distinct geological regions, the Albanian Alps and Mirdita Highlands. A dominant feature of the region's landscape is the presence of several u-shaped valleys, such as the Valley of Valbonë, formed by the process of glaciation. The Albanian Alps are the southernmost extension of the Dinaric Alps and simultaneously the highest and most imposing mountains of the country. Despite the fact that the ice ages had relatively little geological influence on the alps, the southernmost glaciers of Europe were recently discovered on the alps. The Albanian Alps are home to many important rivers of Western Balkans. The main drainage basins of the Alps are those of the Drin and Danube Rivers. Rivers on the Alps fall roughly into two categories, those that flow into the Lim and those that enter the White Drin and meet the Black Drin downstream at the Drin confluence. However, Drin dominates, draining most of the Alps with its tributaries and when measured from the source of the White Drin to the mouth of the Drin near Lezhë. But not all of the Drin flows near or parallel to the Alps. One Drin tributary is the Valbona River, which drains into the Adriatic Sea, and its eastern tributary the Gashi River. The terrain of the central mountain range is predominantly mountainous and extremely fragmented carved into its present shape by the glaciers of the last ice age. The region is dominated by three mountain ranges, each running from north-northeast to south-southwest, roughly parallel to the eastern border of Albania. The Korab Mountains are certainly the most striking feature of the physical geography of the region.