The end of the Bronze Age and Early Iron Age (Hallstatt period, HaC) brought an increase in the rate of cultural development in the Polish territory of Silesia, Great Poland, Kujawy, and Pomerania. The settlement model changed, and fixed settlements – fortifications –appeared. The quantity of the “Lusatian” strongholds in Silesia has changed as research has progressed. We now estimate the number of fortifications in Silesia at about fifteen. Uthenwoldt has extensively discussed the twin fortifications in Silesia, of which only two confirmed fortifications remain today, in Wrocław-Osobowice. The function of these two neighboring complementary fortifications has generated various hypotheses and continues to be the subject of research.