Within historical times, the coast of Pozzuoli, near Naples, has undergone a slow depression that caused the columns of the temple of Serapis to sink into the sea, from which they emerged later through a rising movement of the ground.
In consequence of the earthquake that destroyed Messina and Reggio (28 December, 1908), the ground has undergone alteration, and telluric movements show no tendency to cease.
Glaciers that at one time occupied the greater portion of Northern Italy gave rise to many moraine ranges.
When the promontory of Gargano was an island, the Adriatic Sea, which separated that elevation from the Apennines and which occupied all the table-land of Apulia, projected an arm towards the south through the Sella di Spinazzola and the valley of the rivers Basentiello and Bradano, until it met the Ionian Sea.
It is open towards the Mediterranean, while its south-western limit is a line drawn from Cape Lardier, in Provence, to Cape Revellata in Corsica.
The tides of this sea vary from six to eight inches.
The centre of European interests was carried towards the west: the Italian republics fell into decay, and sea power went to the countries on the Atlantic Ocean.