A road ferry operates on the sea sections of the road. The ferries are yellow and sail short distances between the islands. The longest ferry trip takes about 30 minutes and is between Korpo and Houtskär. All yellow ferries are free of charge. All ferries along the Archipelago Trail, except the Houtskär-Iniö ferry, are yellow and free of charge and do not need to be booked in advance on the day.
There are also ferryboats that serve many different islands along different routes and have their own timetables. Some of these routes are short and take about an hour, and the longest routes take all day. For example, you can take a ferry out to Själö, Brännskär, Utö and Kökar.