Coastlines

The most evident fact when you study a map of Sardinia, is the approximate parallelism of the occidental and oriental coasts. They are predominantly rocky and of different nature (granite and scission, porphyry and chalk, tracyte and basalt.
The height of the banks varies with regard to the relief, the higher found where the banks of chalk reach down to sea level. They can be seen particularly along the coast of Ogliastra, while at Baunei you find the highest cliffs in Europe with the pinnacle of Perda Longa (128m), Punta Giradili (732m), Punta Salinas (320m),Punta Plummare (450m), the Pinnacle of Goloritzè (168m). They are of fascinating beauty with the whiteness of the rock touched by a transparent sea. Among the various coastal habitats you can make an initial distinction: high, rocky coasts and low, sandy coasts; the former make up three quarters of the coastline of the island, the latter, the remaining quarter.
The island's coastlines are of limited submersion and are shaped by the force of the sea. The submersion has caused great changes both in the coastal plains and the low valleys awash with rivers forming "rias", deep inlets in the form of funnels.
The beaches, generally small, are found between the high, rocky coastlines, the major examples can be seen in the gulfs of Oristano, Asinara and Cagliari, in some of these there are high sand dunes (Arbus, Tortolì).
In the north-east part of the island there are high chalk cliffs at Alghero, scissions and granite toward the island of Asinara, while towards the oriental coast we find the "rias" of Stintino, the wide beaches of Valledoria and Badesi and the granite coasts and the "rias" of Gallura.  In the north-east part of the island there are high chalk cliffs at Alghero, scissions and granite toward the island of Asinara, while towards the oriental coast we find the "rias" of Stintino, the wide beaches of Valledoria and Badesi and the granite coasts and the "rias" of Gallura. In the meridian part of the island both in the east and the west, the coast alternates between vast, sandy areas and rocky areas. After the granite coasts of Gallura and the long beaches of Baronia, there is the Gulf of Oroseì, with the basaltic Punta Nera, the beaches and chalk banks that reach as far as Capo Montesanto. Moving south you arrive at a coastal area still relatively unknown by the numerous tourists, called Ogliastra. The suggestive pinnacles of Pedra Longa and Goloritzè reflect in the shallow, crystal-clear waters that break along the long beaches of Lotzorai, Tortolì, Barisardo, Cardedu and Tertenia. In the south of Ogliastra we find a unique beach; it is made up perfectly smooth grey and red pebbles of volcanic origin.