In June 1948 under Soviet Union influence Germany built a wall between East & West Germany:

The question has an error; the Berlin Wall was constructed in 1961, not 1948, by East Germany under Soviet influence to divide Berlin and prevent citizens from escaping to the West. Studying this highlights its role in Cold War tensions, the challenges of ideological divides, and its impact on German history. It also offers insights into how physical barriers reflect political conflicts, providing lessons on diplomacy and reunification efforts to resolve ideological divisions.