Direct sailing from Gdansk to Hel on weekends only in May and June and everyday in July and August. Note in September there will be a daily return service Gdansk - Sopot - Hel, running once a day in each direction.
Tickets can be purchased from the ticket office on the lower quayside near the (C/D-5) Green Gate and cost 40/30zł. Bikes 10zł. Children under 4 travel for free but you'll need to take a 0zl ticket for them.