What was the wall surrounding the eastern europe nations

The Eastern Bloc was the group of socialist states of Central and Eastern Europe, generally the Soviet Union and the countries of the Warsaw Pact. The terms Communist Bloc and Soviet Bloc were also used to denote groupings of states aligned with the Soviet Union, although these terms might include states outside. Hope this helps!!
-K

I am thinking that the answer is the non-literal Iron Curtain that was separating the Eastern and Western European countries from Communism.