CANTABRIAN MOUNTAINS (Span. Cordillera Cantabrica), a mountain chain which extends for more than 300 m. across northern Spain, from the western limit of the Pyrenees to the borders of Galicia, and on or near the coast of the Bay of Biscay. The Cantabrians stretch from east to west, nearly parallel to the sea, as far as the pass of Leitariegos, afterwards trending southward between Leon and Galicia. Their western boundary is marked by the valley of the river Miño (Portuguese Minho), by the lower Sil, which flows into the Miño, and by the Cabrera, a small tributary of the Sil. Some geographers regard the mountains of Galicia beyond the Miño as an integral part of the same system; others confine the name to the eastern half of the highlands between Galicia and the Pyrenees, and call their western half the Asturian Mountains. There are also many local names for the subsidiary ranges within the chain. As a whole, the Cantabrian Mountains are remarkable for their intricate ramifications, but almost everywhere, and especially in the east, it is possible to distinguish two principal ranges, from which the lesser ridges and mountain masses radiate. One range, or series of ranges, closely follows the outline of the coast; the other, which is loftier, forms the northern limit of the great tableland of Castile and Leon, and is sometimes regarded as a continuation of the Pyrenees. The coastal range rises in some parts sheer above the sea, and everywhere has so abrupt a declivity that the streams which flow seaward are all short and swift. The descent from the southern range to the high plateaus of Castile is more gradual, and several large rivers, notably the Ebro, rise here and flow to the south or west. The breadth of the Cantabrian chain, with all its ramifications, increases from about 60 m. in the east to about 115 m. in the west. Many peaks are upwards of 6000 ft. high, but the greatest altitudes are attained in the central ridges on the borders of Leon, Oviedo, Palencia and Santander. Here are the Peña Vieja (8743 ft.), Prieta (8304 ft.) and Espinguete (7898 ft.); an unnamed summit in the Peñas de Europa, to which range the Peña Vieja also belongs, rises on the right bank of the Sella to a height of 8045 ft.; farther west the peaks of Manipodre, Ubiña, Rubia and Cuiña all exceed 7000 ft. A conspicuous feature of the chain, as of the adjacent tableland, is the number of its parameras, isolated plateaus shut in by lofty mountains or even by precipitous walls of rock. At the south-western extremity of the chain is el Vierzo, once a lake-bed, now a valley drained by the upper Sil and enclosed by mountains which bifurcate from the main range south of the pass of Leitariegos - the Sierra de Justredo and Montañas de Leon curving towards the east and south-west, the Sierra de Picos, Sierra del Caurel and other ranges curving towards the west and south-east. The Cantabrians are rich in coal and iron; an account of their geological structure is given under Spain. They are crossed at many points by good roads and in their eastern half by several railways. In the west, near the pass of Pájares, the railway from Leon to Gijón passes through the Perruca tunnel, which is 2 m. long and 4200 ft. above sea-level; the railway descends northward through fifty-eight smaller tunnels. The line from Leon to Orense also traverses a remarkable series of tunnels, bridges and deep cuttings.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)