To 16 ports; the busiest crossings are to Kea (an hour, about four times a day in season), Kythnos (1 hour 10 minutes, about three times a day in season), Kimolos (4 hours, every day in season), Serifos (2½ hours, every day, late May to mid-September), Sifnos (3 hours 10 minutes, every day, late May to mid-September), Agios Efstratios (7¾ hours, four times a week in season), Limnos (9¼ hours, four times a week in season) and Kavala (14¾ hours, four times a week in season).