If the kids like to snorkel, you could add the 'canons' to your North Sound itinerary, especially if the seas are settled. Also fun to watch the kite boarders, if they are there. Be careful of coral heads beyond Saba. Perhaps someone knows if the marker ball is still there at the canons and the directions. I think Oil Nut is closed to boaters until their new marina village is finished, and perhaps in March it may be?
