The Northern Apennine are broken into two sectors: the Ligurian Apennine, and the Emila Romagna are Tuscan Romagnol sector. These mountains have been a natural border between northern and southern Italy for centuries, now we can quickly move through the areas thanks to tunnels and major highways constructed on pillars. The mountains offer several day or multi day hiking routes as well as unique hidden valleys and villages. This is a great place to get off the beaten path in Italy and over the past years there is a push by the Italy Tourism board to develop more recreation areas in the several national parks.
The Northern Apennine mountains run along the coast of Liguria south to La Spezia and then turn east passing through Emilia RomagThe Ligurian Apennines border the Ligurian Sea in the Gulf of Genoa, from about Savona below the upper Bormida River valley to about La Spezia (La Cisa pass) below the upper Magra River valley. The range follows the Gulf of Genoa separating it from the upper Po Valley. The northwestern border follows the line of the Bormida River to Acqui Terme. There the river continues northeast to Alessandria in the Po Valley, but the mountains bend away to the southeast.
The upper Bormida can be reached by a number of roads proceeding inland at a right angle to the coast southwest of Savona, the chief one being the Autostrada Torino-Savona. They ascend to the Bocchetta di Altare, sometimes called Colle di Cadibona, , the border between the Ligurian Alps along the coast to the west and the Ligurian Apennines. A bronze plaque fixed to a stone marks the top of the pass. In the vicinity are fragments of the old road and three ruins of former fortifications.
At Carcare, the main roads connect with the upper Bormida valley (Bormida di Millare) before turning west. The Scrivia, the Trebbia the Taro and the Tanaro (Tanarus), tributaries of the Po River, drain the northeast slopes. The range contains dozens of peaks. Toward the southern end the Aveto Natural Regional Park includes Monte Penna. Nearby is the highest point of Ligurian Apennines, Monte Maggiorasca.
The main overland route connecting the coastal plain of Liguria to the north Italian plain runs through Bocchetta di Altare. It has always been of strategic importance. Defenders of north Italy have had to control it since ancient times, as the various fortifications placed there testify. Currently however, Trenitalia, the state railway system, highly developed on the coastal plain, traverses the mountains routinely through a number of railway tunnels, such as the one at Giovi Pass.
The southeastern border of the Ligurian Apennines is the Fiume Magra, which projects into the Tyrrhenian Sea south of La Spezia, and the Fiume Taro, which runs in the opposite direction to join the Po River. The divide between the two upper river valleys is the Passo della Cisa. Under it (two tunnels) runs the Autostrada della Cisa between Spezia and Parma.
Starting at Cisa Pass, the mountain chains turn further to the southeast to cross the peninsula along the border between the Emilia-Romagna and Tuscany regions. They are also named the Tuscan-Emilian Apennines west of the Futa pass and the Tuscan-Romagnol Apennines east of it, or just the Tuscan Apennines. They extend to the upper Tiber River. The high point is Monte Cimone.
A separate branch, the Apuan Alps, goes to the southwest bordering the coast south of La Spezia. Whether they are to be considered part of the Apennines is a matter of opinion; certainly, they are part of the Apennine System. Topographically only the valley of the River Serchio, which running parallel to the coast turns and exits into the Tyrrhenian Sea north of Pisa, separates the Apuan Alps from the Apennines; geologically the rock is of a slightly different composition: marble. The Roman marble industry was centered at Luna, and is now active in Carrara.
As the Tuscan Apennines divide the peninsula between the Po Valley and the plains and hills of Tuscany and Lazio, transportation over them is essential to political and economic unity. Historically the Romans used the Via Flaminia between Rome and Rimini. The mountain distance between Florence in Tuscany and Bologna in Emilia-Romagna is shorter, but exploitation of it required the conquest of more rugged terrain, which was not feasible for the ancients. Railway lines were constructed over the mountains in the early 19th century but they were of low capacity and unimprovable. Since 1856 a series of tunnels have been constructed to conduct "the Bologna-Florence rail line", which is neither a single line nor a single tunnel. The Porrettana Line went into service in 1864, the Direttissima in 1934 and the High Speed in 1996. A few dozen tunnels support the three of them, the longest on the High-Speed Line being the Voglia Tunnel. The longest is on the Direttissima, the Great Apennine Tunnel, which at is the longest entirely within Italy, although the Simplon Tunnel, which connects Italy and Switzerland, is longer. Claims of being the longest or second-longest in the world have been outdated. Currently automobile traffic is carried by the Autostrada del Sole, Route A1, which goes through numerous shorter tunnels, bypassing an old road, originally Roman, through Futa Pass. The southernmost limit of the Tuscan-Romagnol Apennines is approximately Foreste Casentinesi, Monte Falterona, Campigna National Park. The three-way intersection of the borders between Emilia-Romagna, Tuscany and Marches is on the south slopes of Monte Fumaiolo, from which the Tiber River originates. Monte Fumaiolo is the furthest south mountain of Emilia-Romagna.