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.
Prehistory and origin of Stockholm
As ice lightened its grip of the area about 11,500 BCE, the area was inundated by melt water before the land started to rise and the first islets rose over the water surface (at the time located about 40 metres over the present sea level). The retiring ice left behind a cover of sand, gravel, and rocks forming moraine ridges still witnessing how the ice gave up some 250 m annually over two centuries. Under the ice sheet, streams formed eskers, most notably the huge Brunkebergsåsen, the steep slopes of which still form barriers in central Stockholm.