Yacht sails near Saronic Gulf of Aegean Sea near Athens, Greece

A yacht sails near the Saronic Gulf of the Aegean Sea near south coast of Athens, Greece, June 8, 2018. Greek seas and coastline, a national asset for the Mediterranean country, are threatened by the plastics pollution and climate change, local experts warned on the occasion of the World Oceans Day marked on Friday. (Xinhua/Lefteris Partsalis)