Riddarfjärden
Riddarfjärden (, "The Knight Firth") is the easternmost bay of Lake Mälaren in central Stockholm. Stockholm was founded in 1252 on an island in the stream where Lake Mälaren (from the west) drains into the Baltic Sea (to the east); today the island is called Stadsholmen and constitutes Stockholm's Old Town.
Gamla stan
Gamla stan (, "The Old Town"), until 1980 officially Staden mellan broarna ("The Town between the Bridges"), is the old town of Stockholm, Sweden. Gamla stan consists primarily of the island Stadsholmen. Officially, but not colloquially, Gamla stan includes the surrounding islets Riddarholmen, Helgeandsholmen, and Strömsborg.