APENNINES (Ital. .4 ppennino ; Lat. Mons Apennines, Apennine Mount, from Cym. Celt. , sum • pen, unit, promontory). A mountain chain belonging to the system of the Alps and extending uninterruptedly throughout the whole length of the Italian peninsula. It branches out from the Maritime Alps at the Col di Tenda, near the sources of the Tanaro. From this point the chain, under the name of the Ligurian Apen nines, girdles the Gulf of Genoa in the imme diate vicinity of the sea, and then runs slightly south of east inland almost across the peninsula at latitude 44°, and then southeastward, forming the watershed between the Adrialie and the Med iterranean, but gradually approaching the east ern coast, till, in the highlands of the Abruzzi, it borders close upon it ; after which it takes a more southerly direction, traversing Calabria, dips under the sea at the Strait of Messina, and reappears on the northern coast of Sicily. The total length is about 800 miles, and the breadth varies from 25 to 85 miles.
Geographers divide the Apennines as follows: (1) The North Apennines, from the Col di Ten da, in the Maritime Alps, to the pass of forgo San Sepolero, in the neighborhood of Arezzo, on the eastern border of Tuscany. (2) The Cen tral Apennines, from Arezzo to the valley of the Pescara, which flows between the two Abruzzi. (3) The South Apennines, from the valley of the Pescara to Cape Spartivento. (4) The Insular Apennines, or the Sicilian Range. The leading feature of the Apennines, wherever they approach the coast, is their extraordinarily steep declivi ties; while in Middle Italy and the adjoining portions of Upper and Lower Italy, long,terraeed plateaus, lower ranges, and filially, relatively extensive coast plains mark their gradual de scent on the west. The general name for these lower ranges is Sub-Apennine; but they have a variety of specific designations, such as the moun tains of Carrara and Seravezza, Protomagno, and Monte Amiata, in Tuscany; the Sabine, Alban, and Volscian mountains in the former Papal States; Monte Gargano on the southeastern coast, north of Manfredonia, etc. The main
chain of the Apennines does not send off spurs into the Apulian Peninsula or heel of Italy, which in the main is rather level, or only interspersed with detached groups of hills. The principal chain exhibits for the most part a dreary and barren appearance, somewhat like a vast wall, with very few projecting peaks to break the dull monotony of the scene, and there fore seldom furnishes any salient points on which the eye of the spectator can rest with pleasure. Naked, riven, covered with thick d6bris, the de clivities seem as if scorched by the southern sun. Only in the Abruzzi, in the Sub-Apennines, and especially in the marble-bearing mountains of Carrara and Seravezza do the bold and magnifi cent forms of the Alps reappear.
The average height of the entire chain of the Apennines is about 4000 feet, which, however, in the north sinks down to little more than 3500 feet, and in the mountains of the Abruzzi rises to 7000 feet. Here, in Monte Corno, the highest peak of the range, forming part of the Gran Sasso d'Italia, they reach an elevation of 9580 feet. The North Apennines attain in Monte Ci alone, situated in the Province of Modena, a height of 7103 feet. The highest peak of the South Apennines is Monte Polino, with an eleva tion of 7450 feet.
The Apennines are pierced by thirteen prin cipal passes. These are, proceeding from north to south: (1) the pass of Savona ; (2) of Boc chetta: (3) of Cisa ; (4) of Monte Cimone; (5) of Poretta; (6) of Pietramala ; (7) of Borgo San Sepolcro: (8) of Fulda; (9) of Serravalle; (10) of Aquila; (11) of lsernia; (12) of Arcano and Trots; (13) of Potenza.