A beautiful low-lying island covered with thick pine forest, Gällnö is the archipelago at its best. Home to just thirty people, a couple of whom farm the land near the jetty, Gällnö has been designated a nature reserve: you can spot deer in the forest or watch eider ducks diving for fish. The youth hostel is well signposted from the main village, where there’s also a small shop selling provisions. From here, there’s the choice of two walks: either head east through the forest for Gällnönäs, from where you can pick up boats back to Stockholm or further out into the islands, or continue past the youth hostel, following signs for Brännholmen until you arrive at a small bay popular with yachties. Look for the hut where the toilet is, as one of its walls bears a map and sign on the outside showing the path leading from here to the row-boats – these enable you to cross the narrow sound (around 15m wide) separating Gällnö from its neighbour, Karklö. When you head across, remember to leave one boat on either side of the sound.