In the west, there were a series of smaller Slav peoples that warred and traded with the Germans and Saxons. The Polanie were undisturbed throughout the eighth and ninth centuries. These people were all considered primative, but they had earthworks and places or worship. They also had open cast mining and iron smelting. Because this settlement was water-logged, the plan of the streets and houses were preserved in much detail.
Scholars now believe that it was originally an island.
In 500 BC the water level rose and it was buried. They first noticed timbers portruding from Lake Biskupin. This fortress was build on a peninsula that went into Lake Biskupin. Many small lakes dot this terrain. The terrain was marshy peat, so wooden supports were sunk deep below the surface, to keep the houses and walls upright.