Walker - 1967 - A geography of Italy

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PART III: REGIONAL G E O G R A P H Y
Pistoia has been supplemented since the thirties by the Prato route which involves
a very long tunnel. Away from the Via Emilia, Ferrara (154,000), once
entirely dependent on agriculture, now shares in the chemical industry and
Ravenna (116,000), thanks to petro-chemicals, is rising rapidly from its Byzantine
tomb; the splendour o f its mosaics are a unique attraction for the hosts of
tourists on their way to the beaches o f Rimini, Riccione and Cattolica.
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I I I L IG U R IA
Along the entire Ligurian coast there is no compromise between the mountains
and the sea. 65% o f the regione is classed as motmtainous and 35% as hilly, but
very occasionally, as at Albenga and Diano Marina, the moimtains fall back to
tolerate a narrow lowland, usually where a torrent pauses briefly on an alluvial
flat. Communications along the coast have been established only with the
greatest dififlculty; the railway is punctuated with tunnels, and although a scenic
road is now being hacked through the Cinque Terre, the Via Aurelia has to
abandon the coast altogether between Sestri Levante and La Spezia. T o avoid
congestion the autostrada (completed so far only between Savona and Voltri) is
being carried along the mountain flank high above the shore. A dozen tortuous
roads force their way over the watershed but the vast majority o f the traflSc inland
is channelled into the Altare (459m), Giovi (472m) and Cisa (1039m) passes; all
three are exploited by railways and roads, and by autostrade in the case of the
first two. A fourth railway line approaches Genoa tmder the Turchino Pass.
It is the convention to divide the Alps and the Apennines at the Altare Pass.
Bearing in mind the strong afiinities o f the rocce verdi between Savona and Genoa
with those of the Piedmontese Alps, geologists prefer to make the break at the
Giovi, and there is much to be said for treating the Riviera di Ponente separately
from the Riviera di Levante. The former exhibits a greater variety o f rock type
and landform, is drier, milder and more sheltered. Between Tenda, Ventimiglia
and Albenga the landscape is developed on erodible Eocene sandstones and
marls, and although the terrain is often steep it is hilly rather than mountainous.
Inland between Savona and Albenga, where the Maritime Alps reach to 1386m
in M . Settipani and to 2630m in Mongioie, the relief is shared by Carboniferous
sandstones, Permian limestones and porphyries o f similar age; caverns and other
imderground karstic features are well developed in the limestones. In the
‘Alpine’ sector o f the Ligurian Apennines, where the range is at its narrowest and
lowest, the component rocks are gneisses, schists and rocce verdi, among which
serpentines often emerge as isolated resistant masses (M. Beigua). Here, as in so
much o f Liguria, short torrents, revived by the post-Pliocene uplift, have cut
steep-sided valleys in rocks which are inherently unstable. Soil erosion has been
the inevitable consequence o f deforestation, and the agricultural land of the
lower slopes owes its survival to systems o f terraces evolved over the centuries.
I f anything the rocks o f the Riviera di Levante and its liinterland are even more
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