During the entire summer season, you can take boat trips in the archipelago of Bamble. You can combine the boat trips with coastal walks, restaurant visits, and shopping.
The Helgeroa ferries start their season on June 24th and run on a fixed route between Helgeroa and Langesund until August 14th. Breviksfergene has fixed summer routes with MS Løyøy to the islands in the archipelago of Langesundsfjorden from June 24th until August 14th. Archipelago cruises from Langesund to Valle run on a fixed schedule throughout July. This needs to be booked in advance.
You can book charter trips throughout the year with Helgeroafergene and with MS Dikkon.