APENNINES, a range of mountains traversing peninsular Italy, forming the backbone of the country (Gr., 'Aith'v Vos, Lat. Appenninus—in both cases used in the singular). The name probably derives from Celtic pen, a mountain top : it originally belonged to the northern part, from the Maritime Alps to Ancona. Polybius probably first applied it to the whole chain, extending the name as far as Marseille. Classical authors use the name for the whole. The total length is some Boom. and the maximum width 7o to 8om.
Divisions.—Modern geographers divide the range into three parts, northern, central and southern. I. The Northern Apen nines stretch from the Maritime Alps at the Bocchetta dell'Altare, some 5m. W. of Savona on the high road to Turin. They are divided into Ligurian, Tuscan and Umbrian Apennines. The Ligurian Apennines extend as far as the pass of La Cisa in the upper valley of the Magra (anc. Macra) above Spezia; at first they follow the curve of the Gulf of Genoa, and then run south east parallel to the coast. On the north and north-east the Ligurian Apennines give rise to Scrivia (Olubria), Trebbia (Trebia) and Taro (Tarns), feeders of the Po. The Tanaro (Tanarus), though largely fed by tributaries from the Ligurian Apennines, itself rises in the Maritime Alps. The south side rises steeply from the sea, is fertile and highly cultivated, and has favourite winter resorts (see RIVIERA). Monte Bue reaches 5,915ft. Railways cross from Savona to Turin, from Genoa to Ovada and Asti, the main lines from Genoa to Arquata Scrivia, the junction for Turin and Milan (both the latter pass under the Monte dei Giovi, the ancient Mons Ioventius, by which the ancient Via Postumia ran from Genoa to Dertona), and (a long way farther south-west) that from Spezia to Parma under the pass of La Cisa. All traverse the ridge by long tunnels. The Ligurian Apennines have many hydro electric plants, and arrangements have been made for interchange between them and the Alpine plants as required.
The Tuscan Apennines extend from the pass of La Cisa to the sources of the Tiber. The main chain continues to run east-south east across the peninsula. Many streams run north and north east into the Po, including the Secchia (Secia) and Panaro (Scul tenna) ; farther east, most of the rivers feed the Reno (anc. Rhenus). The Ronco (Bedesis) and Montone (Utis), which flow into the sea together east of Ravenna, were also tributaries of the Po; and the Savio (Sapis) and the Rubicon seem to be the only streams from this side of the Tuscan Apennines that ran directly into the sea in Roman days. From the south-west side the Arno (q.v.) and Serchio run into the Mediterranean. Rail ways cross from Pistoia and Bologna and from Florence to Faenza (while a direct line from Prato to Bologna will soon be completed) and the direct road from Florence to Bologna over the Futa pass is Roman. Monte Cimone reaches 7,103ft. The so-called Alpi Apuane (the Apuani were an ancient people of Liguria), a de tached chain south-west of the valley of the Serchio, rise to a maximum height of 6,IOOft. They contain the famous marble quarries of Carrara. Tuscany, however, is taken up by lower hills, divided from the Apennines by the Arno, Chiana (Clania) and Paglia (Pallia). Towards the west they are rich in minerals and chemicals which the Apennines proper do not produce.
The Umbrian Apennines extend from the sources of the Tiber to about the pass of Scheggia near Cagli, where the ancient Via Flaminia crosses the range. Monte Nerone reaches 5,oloft. The chief river is the Tiber. The Foglia (Pisaurus), Metauro (Metau rus) and Esino (anc. Aesis, the boundary of Italy proper, 3rd and and centuries B.e.) run north-east to the Adriatic. The railway crosses from Foligno to Ancona. 2. The Central Apennines stretch as far as the valley of the Sangro (Sangrus). To the north are the Monti Sibillini, with highest point Monte Vettore (8,128f t.) . Of three parallel chains farther south, the Monte Sabini to the west has Monte Viglio (7,o7 5f t. ), the central chain has Monte Termi nillo (7, 26of t. ), and, to this, Monte Velino (8, i 6of t. ), the eastern chain has the Monte Maiella (M. Amaro 9,I7oft.) and the highest summit of all, Gran Sasso d'Italia (9, 56of t.) . Between the west ern and central ranges are the plain of Rieti, the valley of the Salto (Hiynella), and the Lago Fucino; between the central and east the valleys of Aquila and Sulmona. The chief western rivers are the Nera (Nar) and Anio, both feeding the Tiber. On the east small rivers flow about 25m. or less to the Adriatic. The Pescara (Aternus) and Sangro are more important. Railways cross from Rome to Castelammare Adriatico via Avezzano and Sulmona : from Orte to Terni and Foligno via the Nera valley; from Terni and the plain of Rieti to Aquila and the valley of the Aterno to Sulmona. The Via Salaria, Via Caecilia and Via Claudia Valeria all ran from Rome to the Adriatic coast. The volcanic mountains of the province of Rome are separated from the Apennines by the Tiber, and the Monti Lepini, or Volscian moun tains, by the Sacco and Liri. 3. In the Southern Apennines, south of the Sangro valley, the three parallel chains break into small groups; including the Matese, with Monte Miletto (6, 7 2 5f t.) . The chief rivers on the south-west are Liri or Garigliano (anc. Liris), with tributary the Sacco (Trerus), Volturno (Volturnus), Sebeto (Sabatus), Sarno (Sarnus), on the north Trigno (Trinius), Biferno (Tifernus), and Fortore (Frento). Monte Gargano on the east is completely isolated, and so are the volcanic groups near Naples. Railways cross from Sulmona (N.W.) to Benevento and on to Avellino (S.E.), and from Caianello (S.W.) via Isernia to Campobasso and Termoli (N.E.), from Caserta to Benevento and Foggia, and from Nocera and Avellino to Rocchetta S. An tonio, the junction for Foggia, Spinazzola (for Barletta, Bari, and Taranto) and Potenza. Roman roads followed the same lines, the Via Appia from Capua to Benevento, whence the older road went to Venosa and Taranto and so to Brindisi, while the Via Traiana ran nearly to Foggia and thence to Bari.
The Ofanto (Audfidus) reaching the Adriatic near Barletta, is the northern end of the first range of the Lucanian Apennines (now Basilicata), which runs from east to west, while south of the Sele (W.) and Basento (E.), with the railway from Batti paglia via Potenza to Metaponto, the second range runs due north and south to the plain of Sibari (Sybaris). Monte Pollino reaches 7,3 2 5f t. The chief western rivers are Sele (Silarus), joined by Negro (Tanager) and Calore (Calor) ; Bradano (Bra danus), Basento (Casuentus), Agri (Aciris), Sinni (Siris) on the east flow into the Gulf of Taranto. South of this the land is too narrow for large streams. The railway south from Sicignano to Lagonegro, up the valley of the Negro, is to extend to Cosenza, along the line of the Via Popilia, which beyond Cosenza reached the west coast of Terina and thence followed it to Reggio. The Via Herculia, a branch of the Via Traiana, ran from Aequum Tuticum to the ancient Nerulum. On the east the plain of Sibari with the Coseile (Sybaris) and Crati (Crathis) rivers extends half across the peninsula at its narrowest. A railway (with branches north to Castrovillari and south to Cosenza and the Sila) crosses the isthmus to Paola. Here the limestone Apennines proper cease and the granite mountains of Calabria (anc. Brut tii) begin. The first group of the granite Apennines beyond this is the Sila with the Botte Donato (6,33oft.). Its forests supplied Greeks and Sicilians with timber for shipbuilding. The railway from Santa Eufemia to Catanzaro and Catanzaro Marina crosses the isthmus, and an ancient road may have run from Squillace to Monteleone. The second group, the southern end of Italy, culmi nates in the Aspromonte (6,42oft.), in the Sila range east of Reggio di Calabria.
Character.—The forests were probably larger of old. (Pliny mentions especially pine, oak and beech woods) ; serious attempts at reafforestation have been made but much remains to be done. Summer pasture occurs especially in the Abruzzi : Pliny praises the cheese of the Apennines. In the forests wolves were frequent, and still are found, the flocks being protected by large sheep dogs; bears, known in Roman times, have almost entirely dis appeared, wild goats called rotae, named by Varro, do not occur now. Brigandage was a feature in remoter parts of the Apennines from Roman times. Snow lies long on the highest Apennines. There are no minerals but a considerable number of good mineral springs, some thermal (Bagni di Lucca, Montecatini, Monsum mano, Porretta, Salso maggiore, Sila, Telese, etc.), others cool (Nocera, Sangemini, Cinciano, etc.). (T. A.) The Apennines form a part of the Alpine-Himalayan group of mountains (see ALPS). The exact correlation of the indi vidual units in this south-western section is still uncertain. Ac cording to Termier (.191 1), the Apennines, with the Atlas moun tains form a system distinct from and lying between the Alpine and the Dinaride branches. Kober (1923) considers them (Apen nine-Atlas) as part of the Dinaride branch, separated from the Alpine by the Corso-Sardinian Massif (Tyrrhenis), an exposed part of an Hercynian Range ("Between Mountains"). Accord ing to Argand (1924), the Pennine Zone extends as far south as the Tuscan coast, the rest of the Apennines belonging to the Dinaride branch. There is also a difference of opinion regarding the application of the theory of exotic overthrusts in the Apen nines, some authorities considering that a straightforward in situ explanation is the more legitimate.
The Apennines consist almost entirely of Triassic, Jurassic, Cretaceous, Eocene and Miocene beds, like the outer zones of the Alps. Remnants of older rocks may be seen in the Calabrian peninsula, Cape Circeo and the island of Zannone, in the Apuan Alps, in the islands off the Tuscan coast and in the Catena Metallifera. These remnants do not all belong to the Apennines. In the south the deposits from the Trias to middle Eocene con sist mainly of limestones, and were laid down, with a few inter ruptions, upon a quietly subsiding sea-floor. Toward the end of the Eocene, the folding which gave rise to the existing chain be came marked. The sea grew shallow, the deposits became con glomeratic and shaly, and volcanic eruptions began. Folding and elevation went on until the close of the Miocene period, when a considerable subsidence took place and the Pliocene sea over spread the lower portions of the range. Subsequent elevation, without folding, has raised the Pliocene beds in some cases to over 3,000f t. and they now lie almost undisturbed upon the older folded beds. The last elevation led to the formation of numerous lakes, now filled by Pleistocene deposits. Both volcanic eruptions and movements of elevation continue to the present day around the shores of the Tyrrhenian sea. In the Northern Apennines the elevation appears to have begun earlier, for here the upper Cretaceous consists largely of sandstones and conglomerates. In Calabria the chain consists chiefly of crystalline and schistose rocks ; it is the Mesozoic and Tertiary zone which has here been sunk beneath the sea. Similar rocks are found beneath the Trias farther north in some of the valleys of the Basilicata. Glaciers no longer exist in the Apennines, but Post-Pliocene moraines have been observed in Basilicata.
relations with the Alpine-Himalayan chain see ALPS. For detailed Geology see C. S. du Riche Preller, Italian Moun tain Geology (1924) in which numerous refs. to papers, etc., are given.
(J. I. P.)