Wanderlust World Wanderlust World The Baltic Basin formed over millions of years through tectonic plate movements and collisions.
During the Pleistocene (starting ~2 million years ago), repeated glaciations depressed the crust, deepening and widening the basin. Advancing and retreating ice sheets eroded the landscape.
~12,000 years ago, the last ice sheet retreated. Meltwater filled the basin, creating a brackish sea connected to the North Sea via narrow straits (Danish straits), yielding its unique low salinity.
Land uplift from ice-weight release continues, altering coastlines—northern shores rise, southern areas subside.
The stable Fennoscandian Shield (north/east) uplifts slowly; the European Plate (south) creates bays, peninsulas, and islands.
The Baltic Sea's distinct character results from this interplay of tectonics, glaciation, rebound, and restricted ocean exchange.