There are two important mountain chains which belong to Italy, the Alps
and the Apennines. The Alps form a semicircular boundary on the north
and afford a formidable barrier against the neighboring countries of
Europe. Starting from the sea at its western extremity, this chain
stretches toward the north for about one hundred and fifty miles, when
it rises in the lofty peak of Mt. Blanc, fifteen thousand feet in
height; and then continues its course in an easterly direction for about
three hundred and thirty miles, approaching the head of the Adriatic
Sea, and disappearing along its coast. It is crossed by several passes,
through which foreign peoples have sometimes found their way into the
peninsula.
The Apennines, beginning at the western extremity of the Alps, extend
through the whole length of the peninsula, forming the backbone of
Italy.