The sea may be deep where it laps the cliffs, but not so much as you get closer to comfortable beach destinations: Cavo and Arenella in Porto Venere, Terrizzo, Punta Secco, the Carlo Alberto coast, and Fornace and Pozzale on Isola Palmaria.
Swimming is, of course, the most popular outdoor sport. By the way, during the summer, there is a day that bathers have permission to test themselves in the channel between the main town and Palmaria due to the suspension of maritime traffic. It is a day of celebration in the name of freedom.
Water sports, such as sailing and kayaking, rightly have their own spaces.