saltsjön is a bay of the baltic sea that extends from stockholm archipelago to the inner city of stockholm. its innermost part reaches the eastern shore of gamla stan at skeppsbrokajen. it is navigable for large craft and the major ferry lines to and from stockholm pass through it. saltsjön is connected to lake mälaren through norrström, through karl johanslussen at slussen, and through hammarbyslussen and hammarbyleden.