The Open Air Festival at the TV Tower This summer, for the fifth time, the festival will take place on the square of the at the foot of the TV tower in a relaxed atmosphere. the 45Hertz Open Air Festival will take place in a relaxed atmosphere at the foot of the TV tower: 17 days, 17 events, up to 20,000 visitors:inside. The festival blends in harmoniously with the Karoviertel and follows three clear values three clear values: tolerance, diversity and cultural variety. The 45Hertz Festival stands for itself: Focus on artists and artists and artists in the middle of the city and in the middle of summer. summer.