To 18 ports; the busiest crossings are to Serui (an hour), Nabire (4 hours), Biak (3 hours), Biak (Mokmer) (25 hours, once a week), Bariwaro (4 hours, twice a month), Poiwai (7½ hours, twice a month), Teba (12 hours, twice a month) and Bagusa (20 hours, twice a month).