Which east bloc country tore down its barbed wire fences, separating it from austria, so that disgruntled east german "vacationers" could escape to western europe in 1989?

The correct answer is Hungary

Hungary had a long history of disliking the Soviet Union and when the Soviet Union finally started loosing its grip on Hungary, they destroyed the barbed wire fence which separated them from Austria and it enabled thousands of people from Eastern Germany who were vacationing in Hungary to cross the border into Austria and seek refuge in Western Europe since Austria was not communist.