Among the most fascinating aspects of the Trieste coastline are the cliffs - high, steep-sided limestone slopes formed by the intense erosive action of the sea, which has created impressive pinnacles, steep gorges, outcrops and towers of rock. Regional Protected Area of Duino is responsible for protecting this special, transitional area where the bio-geographic areas of Central Europe and the Mediterranean meet and where the salt-water of the Adriatic meets the freshwater of the River Timavo.
The shoreline varies from sandy beaches to rocks and inlets, from cliffs to pebble beaches to mudflats. One of the Carso's most exclusive plants, the Centaurea kartschiana, clings to the boulders which have tumbled down to the sea to be exposed to the salt spray and the sun, while the scree-slopes have been colonized by the common sage plant and the Euphorbia wulfenii. Apart from the larger tourist beaches at Sistiana and Grignano, there are many smaller, quiet and hidden beaches which are more difficult to reach but still great for swimming, such as the bay at Canovella degli Zoppoli. The naturalist beach at Costa dei Barbari is one of the most rugged stretches of the entire coast.

Point of interest
The zoppolo, a simple and primitive boat used along the Trieste coastline for centuries, was carved out of a single tree trunk which gave it a hull strong enough to be dragged up onto a rocky Carso shore without harbours or moorings. It was used by peasant farmers both for inshore fishing and to reach coastal farmland inaccessible from the land.