The post boat delivers the mail every working day, all year round. You can join them on a trip. Book your space the day before, by calling the captain on 0046 708421474.
Dannholmen is an island outside Fjällbacka. to get there you need to have a boat or get a boat taxi. Call Patric on 0738493249.
Patric can show you around the islands on a long or short trip. Book here