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.
Storstockholms Lokaltrafik
SL has its origins in AB Stockholms Spårvägar (SS), a city-owned public transit company which started in 1915 by the City of Stockholm with the aim to deprivatize the two separate private tramway networks into one more efficient company. SS would in the late 1920s also acquire private motorbus companies. The first part of the Stockholm Metro was opened in 1950. SS was renamed to SL in January 1967 when the metro, local train, and bus operations in Stockholm County were merged into a single organisation under the supervision of Stockholm County Council. The different mass transit systems within the County had until then been run by different organisations, Statens Järnvägar, private companies and companies owned by the local municipalities.