The rising land
13,500 years ago the whole of Roslagen lay beneath the ice sheet, and after that beneath the sea. When the ice released its weight the land slowly began to rise – and it still does, by roughly half a centimetre every year. Drag the time slider and watch the archipelago rise out of the sea.
Laddar kartan…
Blue = sea and ice lakes, white = ice sheet at the selected time. The thin outline shows today’s coastline for reference. Shoreline displacement: SGU (CC0). Map background © OpenStreetMap.
Why the land is rising
During the last ice age the kilometre-thick ice sheet pressed the earth’s crust down. When the ice melted some 11,000 years ago the ground began to spring back – a process called post-glacial rebound (isostatic recovery).
In Roslagen the land is still rising by a good 5 millimetres a year. That means shallow bays slowly turn into fields, jetties end up on dry land and the map of the archipelago is quietly redrawn. Many of Roslagen’s oldest places once sat at the water’s edge – today they lie well inland.