Saltsjön is a bay of the Baltic Sea

Baltic Sea

The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...

 that extends from Stockholm archipelago

Stockholm archipelago

The Stockholm archipelago is the largest archipelago of Sweden, and one of the largest archipelagos of the Baltic Sea.-Geography:The archipelago extends from Stockholm roughly 60 kilometers to the east...

 to the inner city of Stockholm

Stockholm

Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...

. Its innermost part reaches the eastern shore of Gamla stan

Gamla stan

Gamla stan , until 1980 officially Staden mellan broarna , is the old town of Stockholm, Sweden. Gamla stan consists primarily of the island Stadsholmen. The surrounding islets Riddarholmen, Helgeandsholmen, and Strömsborg are officially part of, but not colloquially included in, Gamla stan...

 at Skeppsbrokajen

Skeppsbrokajen

Skeppsbrokajen is a quay and a harbour in central Stockholm, Sweden. Passing along Skeppsbron, it forms the east waterfront of the old town Gamla stan....

. It is navigable for large craft and the major ferry lines to and from Stockholm pass through it. Saltsjön is connected to Lake Mälaren

Mälaren

Lake Mälaren is the third-largest lake in Sweden, after Lakes Vänern and Vättern. Its area is 1,140 km² and its greatest depth is 64 m. Mälaren spans 120 kilometers from east to west...

 through Norrström

Norrström

Norrström in central Stockholm connects Lake Mälaren with the Baltic Sea. It runs from Riddarfjärden, north of Gamla stan, to Saltsjön. Two islands lie within it, Strömsborg and Helgeandsholmen. It is one of two natural waterways between Mälaren and the Baltic sea, the other being Söderström south...

, through Karl Johanslussen

Karl Johanslussen

Karl Johanslussen is a lock and a sluice, connecting and controlling the flood discharge between Riddarfjärden, the easternmost part of Lake Mälaren, and Saltsjön, the section of the Baltic Sea reaching into central Stockholm, Sweden. The lock is 75 meters long, 10 meters wide and 3.90 meters deep...

 at Slussen

Slussen

Slussen is an area of central Stockholm, connecting Södermalm and Gamla stan. The area is named after the locks between Lake Mälaren and the Baltic Sea. The locks themselves allow passage between these two bodies of water...

, and through Hammarbyslussen and Hammarbyleden.

Saltsjö or Saltsjön may also denote other parts of the Baltic in the Stockholm region, as opposed to Mälaren or inland lakes. The word appears as part of place names such as Saltsjöbaden

Saltsjöbaden

Saltsjöbaden is a locality situated in Nacka Municipality, Stockholm County, Sweden with 8,937 inhabitants in 2005. It is located on the coast of the Baltic Sea.- History :...

, Saltsjö-Boo or Saltsjö-Duvnäs which are not related to Saltsjön proper.